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  • 1.
    Acker, Pascal
    et al.
    University of Freiburg, Germany.
    Rzesny, Luisa
    University of Freiburg, Germany.
    Marchiori, Cleber F. N.
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet.
    Esser, Birgit
    University of Freiburg, Germany.
    π-Conjugation Enables Ultra-High Rate Capabilities and Cycling Stabilities in Phenothiazine Copolymers as Cathode-Active Battery Materials2019In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 29, no 45, article id 1906436Article in journal (Refereed)
    Abstract [en]

    In recent years, organic battery cathode materials have emerged as an attractive alternative to metal oxide–based cathodes. Organic redox polymers that can be reversibly oxidized are particularly promising. A drawback, however, often is their limited cycling stability and rate performance in a high voltage range of more than 3.4 V versus Li/Li+. Herein, a conjugated copolymer design with phenothiazine as a redox‐active group and a bithiophene co‐monomer is presented, enabling ultra‐high rate capability and cycling stability. After 30 000 cycles at a 100C rate, >97% of the initial capacity is retained. The composite electrodes feature defined discharge potentials at 3.6 V versus Li/Li+ due to the presence of separated phenothiazine redox centers. The semiconducting nature of the polymer allows for fast charge transport in the composite electrode at a high mass loading of 60 wt%. A comparison with three structurally related polymers demonstrates that changing the size, amount, or nature of the side groups leads to a reduced cell performance. This conjugated copolymer design can be used in the development of advanced redox polymers for batteries.

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  • 2.
    Aderne, Rian E.
    et al.
    Pontifícia Universidade Católica do Rio de Janeiro – PUC-Rio, BRA.
    Borges, Bruno Gabriel A. L.
    Universidade Federal do Rio de Janeiro-UFRJ, BRA.
    Avila, Harold C.
    University of Atlantic, COL.
    von Kieseritzky, Fredrik
    Karolinska Institutet.
    Hellberg, Jonas
    Chemtron AB, Sweden.
    Koehler, Marlus
    Universidade Federal do Paraná-UFPR, BRA.
    Cremona, Marco
    Pontifícia Universidade Católica do Rio de Janeiro – PUC-Rio, BRA.
    Roman, Lucimara S.
    Universidade Federal do Paraná-UFPR, BRA.
    Araujo, Moyses C.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University.
    Rocco, Maria Luiza M.
    Universidade Federal do Rio de Janeiro-UFRJ, BRA.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    On the energy gap determination of organic optoelectronic materials: the case of porphyrin derivatives2022In: Materials Advances, E-ISSN 2633-5409, no 3, p. 1791-1803Article in journal (Refereed)
    Abstract [en]

    The correct determination of the ionization potential (IP) and electron affinity (EA) as well as the energy gap is essential to properly characterize a series of key phenomena related to the applications of organic semiconductors. For example, energy offsets play an essential role in charge separation in organic photovoltaics. Yet there has been a lot of confusion involving the real physical meaning behind those quantities. Experimentally the energy gap can be measured by direct techniques such as UV-Vis absorption, or indirect techniques such as cyclic voltammetry (CV). Another spectroscopic method is the Reflection Electron Energy Loss Spectroscopy (REELS). Regarding data correlation, there is little consensus on how the REELS' energy gap can be interpreted in light of the energies obtained from other methodologies such as CV, UV-Vis, or photoemission. In addition, even data acquired using those traditional techniques has been misinterpreted or applied to derive conclusions beyond the limits imposed by the physics of the measurement. A similar situation also happens when different theoretical approaches are used to assess the energy gap or employed to explain outcomes from experiments. By using a set of porphyrin derivatives as model molecules, we discuss some key aspects of those important issues. The peculiar properties of these porphyrins demonstrate that even straightforward measurements or calculations performed in a group of very similar molecules need a careful interpretation of the outcomes. Differences up to 660 meV (similar to 190 meV) are found comparing REELS (electrochemical) measurements with UV-Vis energy gaps, for instance. From the theoretical point of view, a reasonable agreement with electrochemical measurements of the IP, EA, and the gap of the porphyrins is only obtained when the calculations involve the full thermodynamics of the redox processes. The purpose of this work is to shed light on the differences and similarities of those aforementioned characterization methods and provide some insight that might help one to develop a critical analysis of the different experimental and theoretical methodologies.

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  • 3.
    Axelsson, Martin
    et al.
    Uppsala University.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Huang, Ping
    Uppsala University.
    Araujo, C. Moyses
    Karlstad University.
    Tian, Haining
    Uppsala University.
    Small Organic Molecule Based on Benzothiadiazole for Electrocatalytic Hydrogen Production2021In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 143, no 50, p. 21229-21233Article in journal (Refereed)
    Abstract [en]

    A small organic molecule 2,1,3-benzothiadiazole-4, 7-dicarbonitrile (BTDN) is assessed for electrocatalytic hydrogen evolution on glassy carbon electrode and shows a hydrogen production Faradaic efficiency of 82% in the presence of salicylic acid. The key catalytic intermediates of reduced species BTDN-. and protonated intermediates are characterized or hypothesized by using various spectroscopic methods and density functional theory (DFT)-based calculations. With the experimental and theoretical results, a catalytic mechanism of BTDN for electrocatalytic H-2 evolution is proposed.

  • 4.
    Benatto, Leandro
    et al.
    Federal University of Paraná, BRA.
    Marchiori, Cleber
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet.
    Koehler, Marlus
    Federal University of Paraná, BRA.
    Molecular origin of efficient hole transfer from non-fullerene acceptors: insights from first-principles calculations2019In: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 7, no 39, p. 12180-12193Article in journal (Refereed)
    Abstract [en]

    Due to the strong exciton binding energy (E-b) of organic materials, the energy offset between donor (D) and acceptor (A) materials is essential to promote charge generation in organic solar cells (OSCs). Yet an efficient exciton dissociation from non-fullerene acceptors (NFAs) began to be observed in D/A blends even at very low driving force for hole transfer (Delta H-h). The mechanism behind this efficient photoinduced hole transfer (PHT) remains unclear since current estimates from calculations of isolated molecules indicate that E-b > Delta H-h. Here we rationalize these discrepancies using density functional theory (DFT), the total Gibbs free energy method and the extended Huckel theory (EHT). First, we employed DFT to calculate E-b for NFAs of three representative groups (perylene diimide derivatives, indacenodithiophene and subphthalocyanines) as well as for fullerene acceptors (FAs). Considering isolated molecules in the calculations, we verified that E-b for NFAs is lower than for FAs but still higher than the experimental Delta H-h in which efficient PHT has been observed. Finding the molecular geometry of the excited state, we also obtain that the structural relaxation after photoexcitation tends to further decrease (increase) E-b for NFAs (FAs). This effect helps explain the delayed charge generation measured in some NFA systems. However, this effect is still not large enough for a significant decrease in E-b. We then applied EHT to quantify the decrease of E-b induced by energy levels coupling between stacked molecules in a model aggregate. We then estimated the number of stacked molecules so that E-b approaches Delta H-h's. We found that small NFA aggregates, involving around 5 molecules, are already large enough to explain the experiments. Our results are justified by the low energy barrier to the generation of delocalized states in these systems (especially for the hole delocalization). Therefore, they indicate that molecular systems with certain characteristics can achieve efficient molecular orbital delocalization, which is a key factor to allow an efficient exciton dissociation in low-driving-force systems. These theoretical findings provide a sound explanation to very recent observations in OSCs.

  • 5.
    Carvalho, Rodrigo P.
    et al.
    Uppsala Universitet.
    Alhanash, Mirna
    Uppsala Universitet; Chalmers tekniska högskola.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Brandell, Daniel
    Uppsala universitet.
    Araujo, C. Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala universitet.
    Exploring Metastable Phases During Lithiation of Organic Battery Electrode Materials2022In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, no 2, article id e202200354Article in journal (Refereed)
    Abstract [en]

    In this work, the Li-ion insertion mechanism in organic electrode materials is investigated through the lens of atomic-scale models based on first-principles theory. Starting with a structural analysis, the interplay of density functional theory with evolutionary and potential-mapping algorithms is used to resolve the crystal structure of the different (de)lithiated phases. These methods elucidate different lithiation reaction pathways and help to explore the formation of metastable phases and predict one- or multi-electron reactions, which are still poorly understood for organic intercalation electrodes. The cathode material dilithium 2,5-oxyterephthalate (operating at 2.6 V vs. Li/Li+) is investigated in depth as a case study, owing to its rich redox chemistry. When compared with recent experimental results, it is demonstrated that metastable phases with peculiar ring-ring molecular interactions are more likely to be controlling the redox reactions thermodynamics and consequently the battery voltage.

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  • 6.
    Carvalho, Rodrigo P
    et al.
    Uppsala university.
    Marchiori, Cleber
    Uppsala universitet.
    Araujo, Moyses
    Uppsala universitet.
    Brandell, Daniel
    Uppsala university.
    Atomic-scale Modelling of Redox-active Organic Molecules and Polymers for Energy Applications2020In: Redox Polymers for Energy and Nanomedicine / [ed] Nerea Casado, David Mecerreyes, Royal Society of Chemistry, 2020, p. 93-136Chapter in book (Other academic)
  • 7.
    Carvalho, Rodrigo P.
    et al.
    Uppsala University.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Brandell, Daniel
    Uppsala University.
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University.
    Artificial intelligence driven in-silico discovery of novel organic lithium-ion battery cathodes2022In: Energy Storage Materials, ISSN 2405-8289, E-ISSN 2405-8297, Vol. 44, p. 313-325Article in journal (Refereed)
    Abstract [en]

    Organic electrode materials (OEMs) combine key sustainability and versatility properties with the potential to enable the realisation of the next generation of truly green battery technologies. However, for OEMs to become a competitive alternative, challenging issues related to energy density, rate capability and cycling stability need to be overcome. In this work, we have developed and applied an alternative yet systematic methodology to accelerate the discovery of suitable cathode-active OEMs by interplaying artificial intelligence (AI) and quantum mechanics. This AI-kernel has allowed a high-throughput screening of a huge library of organic molecules, leading to the discovery of 459 novel promising OEMs with candidates offering the potential to achieve theoretical energy densities superior to 1000 W h kg(1). Moreover, the machinery accurately identified common molecular functionalities that lead to such higher-voltage electrodes and pointed out an interesting donor-accepter-like effect that may drive the future design of cathode-active OEMs.

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  • 8.
    Carvalho, Rodrigo P.
    et al.
    Uppsala University .
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Brandell, Daniel
    Uppsala University .
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University.
    Understanding the lithiation limits of high-capacity organic battery anodes by atomic charge derivative analysis2022In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 157, no 18, article id 181101Article in journal (Refereed)
    Abstract [en]

    The superlithiation of organic anodes is a promising approach for developing the next generation of sustainable Li-ion batteries with high capacity. However, the lack of fundamental understanding hinders its faster development. Here, a systematic study of the lithiation processes in a set of dicarboxylate-based materials is carried out within the density functional theory formalism. It is demonstrated that a combined analysis of the Li insertion reaction thermodynamics and the conjugated-moiety charge derivative enables establishing the experimentally observed maximum storage, thus allowing an assessment of the structure-function relationships also.

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  • 9.
    Carvalho, Rodrigo P.
    et al.
    Uppsala University.
    Marchiori, Cleber F. N.
    Uppsala University.
    Oltean, Viorica-Alina
    Uppsala University.
    Renault, Steven
    University Nantes, FRA.
    Willhammar, Tom
    Stockholm University.
    Gomez, Cesar Pay
    Uppsala University.
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University.
    Brandell, Daniel
    Uppsala University.
    Structure-property relationships in organic battery anode materials: exploring redox reactions in crystalline Na- and Li-benzene diacrylate using combined crystallography and density functional theory calculations2021In: Materials Advances, E-ISSN 2633-5409, Vol. 2, no 3, p. 1024-1034Article in journal (Refereed)
    Abstract [en]

    Organic-based materials are potential candidates for a new generation of sustainable and environmentally friendly battery technologies, but insights into the structural, kinetic and thermodynamic properties of how these compounds lithiate or sodiate are currently missing. In this regard, benzenediacrylates (BDAs) are here investigated for application as low-potential electrodes in Na-ion and Li-ion batteries. Aided by a joint effort of theoretical and experimental frameworks, we unveil the structural, electronic and electrochemical properties of the Na(2)BDA and Li(2)BDA compounds. The crystal structure of these systems in their different sodiated and lithiated phases have been predicted by an evolutionary algorithm interplayed with density functional theory calculations. Due to difficulties in obtaining useful single crystals for the BDA salts, other methods have been explored in combination with the computational approach. While the predicted structure of the pristine Na(2)BDA compound has been experimentally confirmed through the 3D Electron Diffraction (3DED) technique, the hydrated version of Li(2)BDA is analysed through single crystal X-ray diffraction. The calculated cell voltages for the sodiation (0.63 V vs. Na/Na+) and lithiation (1.12 V vs. Li/Li+) processes display excellent quantitative agreement with experimental findings. These results validate the developed theoretical methodology. Moreover, fundamental aspects of the electronic structures and their relationship with the reaction thermodynamics are discussed. The results suggest a possible disproportionation between the sodiated phases of Na(2)BDA, supporting a two-electron process, and also unveil major differences for the two employed cations: Na+ and Li+.

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  • 10.
    Damas, Giane
    et al.
    Uppsala universitet.
    Marchiori, Cleber
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet.
    Tailoring the Electron-Rich Moiety in Benzothiadiazole-Based Polymers for an Efficient Photocatalytic Hydrogen Evolution Reaction2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 42, p. 25531-25542Article in journal (Refereed)
    Abstract [en]

    Polymeric materials containing an extended π-conjugated backbone have shown a wide range of applicability including photocatalytic activity for the hydrogen evolution reaction (HER). The latter requires highly efficient materials with optimal light absorption and thermodynamic driving force for charge transfer processes, properties that are tailored by linking chemical units with distinct electron affinity to form a donor−acceptor architecture. Here, this concept is explored by means of ab initio theory in benzothiadiazole-based polymers with varying electron-rich moieties, viz., fluorene (PFO), cyclopentadithiophene (CPT), methoxybenzodithiophene (O-BzT), thiophenebenzodithiophene (T-BzT), and thiophene (T, VT)and thienethiophene (TT, VTT)-based units. All materials exhibit a red-shifted absorption spectrum with respect to the reference polymer (PFO-DT-BT) while keeping the catalytic power for hydrogen production almost unchanged. In particular, a displacement ofΔλ = 167 nm in the first absorption maximum has been achieved upon combination of chemical units with high donating character in CPT-VTT-BT. Furthermore, the exciton binding energies (Eb) have been systematically investigated to unveil the effects of geometry relaxation, environment polarity, and finite temperature contributions to the free energy. For instance, we show a significant change in Eb when going from the gas phase (Eb = 1.43−1.85 eV) to the solvent environment (Eb = 0.29−0.54 eV in 1-bromooctane with ε = 5.02). Furthermore, we have found a linear correlation between the lowering of exciton binding energies and the increasing of the ratio between donor and acceptor contributions to the HOMO orbital. This is a consequence of increased donating ability and enhanced spatial separation of electron−hole pairs, which weakens their interaction. Finally, our findings reveal that the donor unit plays a crucial role in key properties that govern the photocatalytic activity of donor−acceptor polymers contributing to the development of a practical guideline to design more efficient photocatalysts for the HER. This goes through a proper combination of electron-rich moieties to tune the optical gap, favor thermodynamic driving force for charge transfer, and lower exciton binding energies.

  • 11.
    Damas, Giane
    et al.
    Uppsala universitet.
    Marchiori, Cleber F. N.
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet.
    On the Design of Donor Acceptor Conjugated Polymers for Photocatalytic Hydrogen Evolution Reaction: First-Principles Theory-Based Assessment2018In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, no 47, p. 26876-26888Article in journal (Refereed)
    Abstract [en]

    A set of fluorene-based polymers with a donor acceptor architecture has been investigated as a potential candidate for photocatalytic hydrogen evolution reaction. A design protocol has been employed based on first -principles theory and focusing on the following properties: (i) broad absorption spectrum to promote a higher number of photogenerated electron hole pairs, (ii) suitable redox potentials, and (iii) appropriate reaction thermodynamics using the hydrogen -binding energy as a descriptor. We have found that the polymers containing a fused -ring acceptor formed by benzo(triazole-thiadiazole) or benzo(triazole-selenodiazole) units display a suitable combination of such properties and stand out as potential candidates. In particular, PFO-DSeBTrT (poly (9,9'-dioctylfluorene)-2,7-diyl-alt-(4,7-bis(thien-2y1)-2-dodecyl-benzo-(1,2c:4,5c')-1,2,3-triazole-2,1,3-selenodiazole)) has an absorption maximum at around 950 nm for the highest occupied molecular orbital lowest unoccupied molecular orbital transition, covering a wider range of solar emission spectrum, and a reduction catalytic power of 0.78 eV. It also displays a calculated hydrogen -binding free energy of Delta G(H) = 0.02 eV, which is lower in absolute value than Furthermore, the results and trends analysis provide guidance for the rational design of novel photo-electrocatalysts. that of Pt (Delta G(H) approximate to -0.10 eV).

  • 12.
    Damas, Giane
    et al.
    Uppsala universitet.
    von Kieseritzky, Fredrik
    Arubedo AB.
    Hellberg, Jonas
    Arubedo AB.
    Marchiori, Cleber
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet.
    Symmetric Small-Molecules With Acceptor-Donor-Acceptor Architecture for Efficient Visible-Light Driven Hydrogen Production: Optical and Thermodynamic Aspects2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 51, p. 30799-30808Article in journal (Refereed)
    Abstract [en]

    Small-molecules (SM) have attracted a great deal of attention in the field of solar energy conversion due to their unique propertiescompared to polymers, such as well-defined molecular weight and lack of regio-isomeric impurities. Furthermore, these materials can be synthesized in a variety of configurational architectures, representing an opportunity for tailoring chemical and optical properties that could lead to a better photocatalytic efficiency for hydrogen generation. Here, we evaluate by means of density functional theory (DFT) and time-dependent DFT methods a set of small-molecules with A-D-A architecture (A-acceptor; D- donor) based on well-known building blocks like thiophene (T), cyclopentadithiophene (CPT) and benzothiadiazole (BT) as potential candidates for photocatalytic hydrogen evolution reaction (HER). We also propose i) the replacement of the thiophene unit by 3,4-ethylenedioxythiophene (EDOT) to form with CPT unit an extended donor core ii) an additional acceptor unit, the 1,3,4-thiadiazole (Tz), in the extremities and iii) insertion of the difluoromethoxy (DFM) as substituent in the BT unit. Our outcomes reveal that these materials have a broad absorption spectrum with λ= 318-719 nm, being the most intense absorption peak originated from an electronic transition with charge-transfer nature, as the spatial distribution of LUMO is concentrated on the acceptor units for all materials. Moreover, these small-molecules not only present catalytic power or thermodynamic driving force to carry out the chemical reactions involved in the process of hydrogen production, but can be coupled in cooperative photocatalytic systems to promote intramolecular charge transfer that is expected to boost the overall photocatalytic efficiency of these materials.

  • 13.
    de Araujo, L. O.
    et al.
    Federal University of Technology, BRA.
    Neto, A. L.
    Federal University of Technology, BRA.
    Scalon, L.
    University of Campinas, Campinas, BRA.
    Rodrigues, P. C.
    Federal University of Technology, BRA.
    Floriano, J. B.
    Federal University of Technology, BRA.
    Araujo, C. M.
    Uppsala University.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Barreto, R. C.
    Federal University of Technology, BRA.
    A new CBD-CC-E spectral similarity scale for optimizing computer-simulated UV–vis spectra2021In: Computational and Theoretical Chemistry, ISSN 2210-271X, E-ISSN 2210-2728, Vol. 1197, article id 113116Article in journal (Refereed)
    Abstract [en]

    A new CBD-CC-E spectral similarity scale is proposed to optimize computer-simulated UV–vis spectra. The scale was tested using the S1←S0 spectrum of the dithienyl-diketopyrrolopyrrole molecule (DPP2T), an important building block for manufacturing materials for optoelectronic applications. Our results indicate that the spectrum calculated at M06/6-311++G(d,p) level was the one that best reproduced the intensity and shape features of the experimental spectrum, while CAM-B3LYP/6-311++G(d,p) was the one that best reproduced the energy. The CBD-CC-E scale makes the comparison between computer-simulated and experimental spectra statistically based, allowing a systematic and automated choice of the theory level whose calculated spectrum best reproduces the shape, intensity or energy of the experimental UV–vis spectrum.

  • 14.
    Ebadi, Mahsa
    et al.
    Uppsala universitet.
    Marchiori, Cleber
    Uppsala universitet.
    Mindemark, Jonas
    Uppsala universitet.
    Brandell, Daniel
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet, Materialteori.
    Assessing structure and stability of polymer/lithium-metal interfaces from first-principles calculations2019In: Journal of Materials Chemistry A, ISSN 2050-7488, E-ISSN 2050-7496, Vol. 7, no 14, p. 8394-8404Article in journal (Refereed)
    Abstract [en]

    Solid polymer electrolytes (SPEs) are promising candidates for Li metal battery applications, but the interface between these two categories of materials has so far been studied only to a limited degree. A better understanding of interfacial phenomena, primarily polymer degradation, is essential for improving battery performance. The aim of this study is to get insights into atomistic surface interaction and the early stages of solid electrolyte interphase formation between ionically conductive SPE host polymers and the Li metal electrode. A range of SPE candidates are studied, representative of major host material classes: polyethers, polyalcohols, polyesters, polycarbonates, polyamines and polynitriles. Density functional theory (DFT) calculations are carried out to study the stability and the electronic structure of such polymer/Li interfaces. The adsorption energies indicated a stronger adhesion to Li metal of polymers with ester/carbonate and nitrile functional groups. Together with a higher charge redistribution, a higher reactivity of these polymers is predicted as compared to the other electrolyte hosts. Products such as alkoxides and CO are obtained from the degradation of ester- and carbonate-based polymers by AIMD simulations, in agreement with experimental studies. Analogous to low-molecular-weight organic carbonates, decomposition pathways through C-carbonyl-O-ethereal and C-ethereal-O-ethereal bond cleavage can be assumed, with carbonate-containing fragments being thermodynamically favorable.

  • 15.
    Ebadi, Mahsa
    et al.
    Uppsala universitet.
    Nasser, Antoine
    Uppsala universitet.
    Carboni, Marco
    Uppsala universitet.
    Younesi, Reza
    Uppsala universitet.
    Marchiori, Cleber
    Uppsala universitet.
    Brandell, Daniel
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet, Materialteori.
    Insights into the Li-Metal/Organic Carbonate Interfacial Chemistry by Combined First-Principles Theory and X-ray Photoelectron Spectroscopy2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 1, p. 347-355Article in journal (Refereed)
    Abstract [en]

    X-ray photoelectron spectroscopy (XPS) is a widely used technique to study surfaces and interfaces. In complex chemical systems, however, interpretation of the XPS results and peak assignments is not straightforward. This is not least true for Li-batteries, where XPS yet remains a standard technique for interface characterization. In this work, a combined density functional theory (DFT) and experimental XPS study is carried out to obtain the C 1s and O 1s core-level binding energies of organic carbonate molecules on the surface of Li metal. Decomposition of organic carbonates is frequently encountered in electrochemical cells employing this electrode, contributing to the build up of a complex solid electrolyte interphase (SEI). The goal in this current study is to identify the XPS fingerprints of the formed compounds, degradation pathways, and thereby the early formation stages of the SEI. The contribution of partial atomic charges on the core-ionized atoms and the electrostatic potential due to the surrounding atoms on the core-level binding energies, which is decisive for interpretation of the XPS spectra, are addressed based on the DFT calculations. The results display strong correlations between these two terms and the binding energies, whereas electrostatic potential is found to be the dominating factor. The organic carbonate molecules, decomposed at the surface of the Li metal, are considered based on two different decomposition pathways. The trends of calculated binding energies for products from ethereal carbon-ethereal oxygen bond cleavage in the organic carbonates are better supported when compared to the experimental XPS results.

  • 16.
    Franco, Leandro R.
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University, Sweden.
    Unveiling the impact of exchange-correlation functionals on the description of key electronic properties of non-fullerene acceptors in organic photovoltaics2023In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 159, no 20, article id 204110Article in journal (Refereed)
    Abstract [en]

    Non-fullerene electron acceptors have emerged as promising alternatives to traditional electron-acceptors in the active layers of organic photovoltaics. This is due to their tunable energy levels, optical response in the visible light spectrum, high electron mobility, and photochemical stability. In this study, the electronic properties of two representative non-fullerene acceptors, ITIC and Y5, have been calculated within the framework of density functional theory using a range of hybrid and non-hybrid density functionals. Screened range-separated hybrid (SRSH) approaches were also tested. The results are analyzed in light of the previously reported experimental outcomes. Specifically, we have calculated the oxidation and reduction potentials, fundamental and optical gaps, the highest occupied molecular orbital and lowest unoccupied molecular orbital energies, and exciton binding energies. Additionally, we have investigated the effects of the medium dielectric constant on these properties employing a universal implicit solvent model. It was found that hybrid functionals generally perform poorly in predicting oxidation potentials, while non-hybrid functionals tend to overestimate reduction potentials. The inclusion of a large Hartree-Fock contribution to the global or long range was identified as the source of inaccuracy for many hybrid functionals in predicting both redox potentials and the fundamental and optical gaps. Corroborating with the available literature, ∼50% of all tested functionals predicted very small exciton binding energies, within the range of ±0.1 eV, that become even smaller by increasing the dielectric constant of the material. Finally, the OHSE2PBE and tHCTHhyb functionals and the optimal tuning SRSH approach emerged as the best-performing methods, with good accuracy in the description of the electronic properties of interest. 

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  • 17.
    Jalan, Ishita
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Genene, Zewdneh
    Chalmers University of Technology, Sweden.
    Johansson, André
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wang, Ergang
    Chalmers University of Technology, Sweden.
    van Stam, Jan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Moons, Ellen
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Donor-acceptor polymer complex formation in solution confirmed by spectroscopy and atomic-scale modelling2023In: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 11, no 27, p. 9316-9326Article in journal (Refereed)
    Abstract [en]

    In all-polymer solar cells, high performance is attributed to the fine-grained morphology of the film in the active layer. However, the mechanism by which this fine-grained morphology is achieved remains unknown. Polymeric non-fullerene acceptors have the potential to restrict the self-aggregation, typical of non-fullerene small molecule acceptors. Here we employed a blend of the polymeric acceptor PF5-Y5 and the donor polymer PBDB-T to investigate the balance between molecular interactions in solution. Temperature-dependent absorption spectra show evidence of temperature-induced disaggregation of both donor and acceptor polymers, where the donor polymer disaggregation depends on the solvent polarity. Concentration-dependent fluorescence spectra of blend solutions display blue-shifted acceptor emission upon dilution, similar to that observed in acceptor solutions, and a decreased tendency for charge transfer from donor to acceptor upon dilution. Excitation spectra of dilute blend solutions contain an increased contribution to the long-wavelength acceptor emission, as compared to pure acceptor solutions, from a chromophore that absorbs in a region where the donor does not absorb. These observations can be explained by donor-acceptor complexation in dilute blend solutions, that is stabilized in more polar solvents. Moreover, the near IR-region of the absorption spectrum could be matched with the calculated electronic excitations of donor-acceptor complexes of PBDB-T and PF5-Y5 oligomers. The results corroborate that the interaction between segments of the donor and acceptor polymer chains favours the formation of donor-acceptor charge transfer complexes, stabilized by hybridization of the molecular orbitals, which reduces the electronic energy. The proposed donor-acceptor complex formation competes with the donor and acceptor self-aggregation and is influenced by the solvent environment. These pre-formed donor-acceptor complexes in low-concentration solutions can be expected to have important consequences on the film morphology of all-polymer blends. The results from this joint experimental-theoretical spectroscopy study provide insights that can guide the design of compatible donor and acceptor polymers for future high-performance organic solar cells.

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  • 18.
    Marchiori, Cleber F.N.
    et al.
    Uppsala universitet.
    Brandell, Daniel
    Uppsala universitet.
    Araujo, Carlos Moyses
    Uppsala universitet, Materialteori.
    Predicting Structure and Electrochemistry of Dilithium Thiophene-2,5-Dicarboxylate Electrodes by Density Functional Theory and Evolutionary Algorithms2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 8, p. 4691-4700Article in journal (Refereed)
    Abstract [en]

    Organic electroactive materials are promising candidates to be TUC used as lithium insertion electrodes in the next generation of environmentally friendly battery technologies. In this work, evolutionary algorithms at interplay with density functional theory calculations have been employed to predict the crystal structure for both delithiated and lithiated phases of dilithium thiophene dicarboxylate (Li2TDC). On the basis of the resulting crystals, electronic structure modifications and voltage profiles for the lithiation process have been calculated. The obtained structure for the delithiated phase showed a well-defined salt layer intercalating the organic components, forming a so-called lithium organic framework (LOF). Upon lithiation, new structures appear which deviate from the LOF as a consequence of the reduction of the S atoms, which coordinate with the additional Li ions. The calculated average potential of similar to 1.00 V vs Li/Li+ is found to be in good agreement with experimental findings. An additional study at the molecular level has also been conducted aiming at gaining insight into the importance of the crystallographic environment on the structural and thermodynamics properties. This strategy is suitable for an initial assessment of the electrochemical process that underlies the lithiation mechanism of electrode materials. Moreover, the employed evolutionary algorithm emerges as a promising tool to predict crystal structures during lithiation, which are otherwise difficult to resolve experimentally.

  • 19.
    Marchiori, Cleber F.N.
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Damas, Giane B.
    Linköpings universitet.
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala universitet.
    Tuning the photocatalytic properties of porphyrins for hydrogen evolution reaction: An in-silico design strategy2022In: Journal of Power Sources Advances, E-ISSN 2666-2485, Vol. 15, article id 100090Article in journal (Refereed)
    Abstract [en]

    Porphyrins constitute a class of attractive materials for harvesting sunlight and promote chemical reactions following their natural activity for the photosynthetic process in plants. In this work, we employ an in-silico design strategy to propose novel porphyrin-based materials as photocatalysts for hydrogen evolution reaction (HER). More specifically, a set of meso-substituted porphyrins with donor-acceptor architecture are evaluated within the density functional theory (DFT) framework, according to these screening criteria: i) broad absorption spectrum in the ultraviolet–visible (UV–Vis) and near infrared (NIR) range, ii) suitable redox potentials to drive the uphill reaction that lead to molecular hydrogen formation, iii) low exciton binding free energy (Eb), and iv) low hydrogen binding free energy (ΔGH), a quantity that should present low HER overpotentials, ideally ΔGH = 0. The outcomes indicate that the Se-containing compound, where the donor ligands are attached to the porphyrin core by the spacer, outstands as the most promising candidate that is presented in this work. It displays a broad absorption in the visible and NIR regions to up to 1000 nm, suitable catalytic power, low Eb (in special in high dielectric constant environment, such as water) and the lowest ΔGH = +0.082 eV. This is comparable, in absolute values, to the value exhibited by platinum (ΔGH = −0.10 eV), one of the most efficient catalysts for HER.

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  • 20.
    Marchiori, Cleber
    et al.
    Uppsala universitet.
    Pereira de Carvalho, Rodrigo
    Uppsala universitet.
    Ebadi, Mahsa
    Uppsala universitet.
    Brandell, Daniel
    Uppsala universitet.
    Araujo, Moyses
    Uppsala universitet.
    Understanding the Electrochemical Stability Window of Polymer Electrolytes in Solid-State Batteries from Atomic-Scale Modeling: The Role of Li-Ion Salts2020In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 32, no 17, p. 7237-7246Article in journal (Refereed)
    Abstract [en]

    After decades of development in Li-ion batteries, solid polymer electrolytes (SPEs) are currently experiencing a renaissance as a promising category of materials to be used in all-solid-state batteries. However, a fundamental understanding of their electrochemical properties in the battery environment is still lacking, which in turn limits the implementation of this prospective solution. With the aim of bridging this knowledge gap, we have assessed, through first-principles thermodynamics calculations based on atomic-scale modeling, the electrochemistry of a range of relevant polymer electrolyte hosts in their pristine form and also when doped with commonly used Li-ion salts. A significant change of the electrochemical stability window upon formation of the polymer/salt complexes was found. The mechanisms of the reduction and oxidation reactions are unveiled and correlated to the electronic structures and molecular structural relaxations. In the reduction process, the salt anions control the potentials due to bond cleavage that stabilize the reduced state. In the oxidation process, the mechanism is different with the charge being stabilized either on the polymer or on the salt anion depending on the complex formed. This assessment of the electrochemical stability of the polymer/salt complexes could serve as a guide for electrolyte design in SPE-based all-solid-state batteries.

  • 21.
    Pereira de Carvalho, Rodrigo
    et al.
    Uppsala universitet, Materialteori.
    Marchiori, Cleber
    Uppsala universitet, Strukturkemi.
    Brandell, Daniel
    Uppsala universitet, Strukturkemi.
    Araujo, Carlos Moyses
    Uppsala universitet, Materialteori.
    Tuning the Electrochemical Properties of Organic Battery Cathode Materials: Insights from Evolutionary Algorithm DFT Calculations2020In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 13, no 9, p. 2402-2409Article in journal (Refereed)
    Abstract [en]

    Several forms of organic materials have arisen as promising candidates for future active electrode materials for Li-ion and post-Li-ion batteries, owing to a series of key features that encompasses sustainability, accessibility, and tunable electrochemical properties by molecular modifications. In this context, a series of organic electrode materials (OEMs) are investigated to further understand their thermodynamic and electronic properties. Through an evolutionary algorithm approach combined with first-principles calculations, the crystal structure of lithiated and delithiated phases of these OEMs and their respective NO2-substituted analogues are predicted. This framework allows a first assessment of their electrochemical and electronic properties and further understanding on the effects of the nitro group in the substituted compounds. NO2 is found to strongly affect structural and thermodynamic aspects during the electrochemical reaction with the reducing equivalents (Li++e(-)), changing the OEM's character from a low-potential anode to a high-potential cathode by creating a localization of the additional electrons, thus resulting in a better-defined redox-active center and leading to a shift in the potential from 0.92 V to 2.66 V vs. Li/Li+.

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  • 22.
    Prasad, Suraj
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Genene, Zewdneh
    Chalmers University of Technology, Sweden.
    Ericsson, Leif
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wang, Ergang
    Chalmers University of Technology, Sweden.
    Moons, Ellen
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Photostability of Y-type electron acceptor molecules and related copolymer2023In: Proceedings Volume 12660, Organic, Hybrid, and Perovskite Photovoltaics XXIV; / [ed] Gang Li, Natalie Stingelin, Ana Flávia Nogueira, Thuc-Quyen Nguyen, Ellen Moons, Barry P. Rand, SPIE - The International Society for Optics and Photonics, 2023, Vol. 12660Conference paper (Refereed)
    Abstract [en]

    The lifetime of organic solar cells critically depends on the photochemical stability of the materials. To shed light on the photostability of novel Y-series electron acceptors, we investigate the evolution of optical properties and composition during one-sun illumination in ambient atmosphere of thin films of the small-molecule acceptor Y5 and its copolymers PF5-Y5 and PYT. We employ UV-vis, Fourier-transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS), to assess changes in these properties as a function of illumination time. UV-Vis spectra show that PF5-Y5 undergoes rapid photobleaching, while the Y5 spectrum remains essentially unaffected even after 30 hours of exposure. The absorption spectrum of PYT, which contains a different co-mer than PF5-Y5, is only weakly affected. XPS C1s spectra of the PF5- Y5 film show a decreasing main peak and the development of a new component after 30 hours exposure, while the Y5 film surface composition remained intact. The photodegradation products of PF5-Y5 are characterized by the presence of new carbonyl groups, emerging as absorption bands in the FTIR spectra, while such spectral changes are absent for the Y5 film, indicating that Y5 is resistant to photooxidation, while PF5-Y5 undergoes photochemical reactions. The faster photodegradation of PF5-Y5 compared to Y5 and PYT raises the question about the role of the copolymer’s BDT moiety in the photooxidation. These new insights on the dependence of the photostability of acceptor molecules on their molecular structure are expected to contribute to the design of stable acceptor copolymers for organic solar cells with long operational lifetimes. 

  • 23.
    Ronchi, Rodrigo M.
    et al.
    Federal University of ABC, BRA.
    Marchiori, Cleber
    Uppsala universitet, Strukturkemi.
    Araujo, Moyses
    Uppsala universitet, Materialteori.
    Arantes, Jeverson T.
    Federal University of ABC, BRA.
    Santos, Sydney F.
    Federal University of ABC, BRA.
    Thermoplastic polyurethane - Ti3C2(T-x) MXene nanocomposite: The influence of functional groups upon the matrix-reinforcement interaction2020In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 528, article id 146526Article in journal (Refereed)
    Abstract [en]

    The recently discovered MXenes are promising candidates as reinforcements for nanocomposites due to their high mechanical properties, thermal and electrical conductivities. These properties are strongly affected by the presence of surface functional groups (-O, -F or -OH), which are related to the synthesis route employed. However, there is a lack of scientific investigations concerning the influence of such functional groups on the MXene/polymer matrix interaction. Therefore, we performed density functional theory calculations to simulate the interaction between Ti3C2 MXenes with different functional groups and thermoplastic polyurethane (TPU) based molecules. It was found that the main interaction mechanisms involved were the formation of hydrogen bonds and pi-pi stacking (in the aromatic ring). Moreover, while fluorine and hydroxyl terminations favored the interaction with TPU, oxygen-terminated MXene has hindered it in three of the four configurations tested. These findings indicate the relevance of controlling the MXenes surface chemistry for improving MXenes/polymer matrixes interactions in nanocomposites.

  • 24.
    Scalon, Lucas
    et al.
    The Federal University of Technology, BRA.
    Leithold Neto, Alfredo
    The Federal University of Technology, BRA.
    Araujo, Luis O.
    The Federal University of Technology, BRA.
    Zaioncz, Soraia
    The Federal University of Technology, BRA.
    Floriano, Joao B.
    The Federal University of Technology, BRA.
    Macedo, Andreia G.
    The Federal University of Technology, BRA.;University Aveiro, PRT .
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Rodrigues, Paula C.
    The Federal University of Technology, BRA.
    Assessing the Donor-Acceptor Nature and the Electrochemical Stability of a Fluorene-Diketopyrrolopyrrole-Thiophene-Based Copolymer2021In: ACS Applied Polymer Materials, ISSN 2637-6105, Vol. 3, no 8, p. 4223-4233Article in journal (Refereed)
    Abstract [en]

    Organic dyes have been studied for applications in large-area, flexible, cheap, and efficient organic electronic devices. Among them, diketopyrrolopyrrole (DPP) has gained attention thanks to its planar structure, photochemical and thermal stability, and easy processability. Also, the electron-withdrawing nature of DPP makes its application attractive in the synthesis of donor-acceptor (D-A) copolymers, with appealing features such as the tunable energy levels and photophysical and electrochemical properties. Inspired by these exciting characteristics, a copolymer was developed based on DPP, thiophene, and fluorene (PFDPP2T). Photophysical and electrochemical studies using both experimental and theoretical approaches were performed aiming to understand the properties of this material, such as, for instance, the D-A characteristic and the outstanding electrochemical stability upon oxidation that enables more than 400 cycles of p-doping. The outcomes unveil fundamental aspects of this class of copolymers, reinforcing their suitability for photo-electrochemical and optoelectronic applications.

  • 25.
    Wu, Jingnan
    et al.
    Chalmers University of Technology, Sweden; Aalborg University, Denmark.
    Ling, Zhaoheng
    King Abdullah University of Science & Technology, Saudi Arabia.
    Franco, Leandro R.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Jeong, Sang Young
    Korea University, South Korea.
    Genene, Zewdneh
    Chalmers University of Technology, Sweden.
    Mena, Josue
    Chalmers University of Technology, Sweden.
    Chen, Si
    King Abdullah University of Science & Technology, Saudi Arabia.
    Chen, Cailing
    King Abdullah University of Science & Technology, Saudi Arabia.
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University, Sweden.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Kimpel, Joost
    Chalmers University of Technology, Sweden.
    Chang, Xiaoming
    King Abdullah University of Science & Technology, Saudi Arabia.
    Isikgor, Furkan H. H.
    King Abdullah University of Science & Technology, Saudi Arabia.
    Chen, Qiaonan
    Chalmers University of Technology, Sweden.
    Faber, Hendrik
    King Abdullah University of Science & Technology, Saudi Arabia.
    Han, Yu
    King Abdullah University of Science & Technology, Saudi Arabia.
    Laquai, Frederic
    King Abdullah University of Science & Technology, Saudi Arabia.
    Zhang, Maojie
    Shandong University, China.
    Woo, Han Young
    Korea University, South Korea.
    Yu, Donghong
    Aalborg University, Denmark.
    Anthopoulos, Thomas D. D.
    King Abdullah University of Science & Technology, Saudi Arabia.
    Wang, Ergang
    Chalmers University of Technology, Sweden.
    On the Conformation of Dimeric Acceptors and Their Polymer Solar Cells with Efficiency over 18 %2023In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773Article in journal (Refereed)
    Abstract [en]

    The determination of molecular conformations of oligomeric acceptors (OAs) and their impact on molecular packing are crucial for understanding the photovoltaic performance of their resulting polymer solar cells (PSCs) but have not been well studied yet. Herein, we synthesized two dimeric acceptor materials, DIBP3F-Se and DIBP3F-S, which bridged two segments of Y6-derivatives by selenophene and thiophene, respectively. Theoretical simulation and experimental 1D and 2D NMR spectroscopic studies prove that both dimers exhibit O-shaped conformations other than S- or U-shaped counter-ones. Notably, this O-shaped conformation is likely governed by a distinctive "conformational lock" mechanism, arising from the intensified intramolecular & pi;-& pi; interactions among their two terminal groups within the dimers. PSCs based on DIBP3F-Se deliver a maximum efficiency of 18.09 %, outperforming DIBP3F-S-based cells (16.11 %) and ranking among the highest efficiencies for OA-based PSCs. This work demonstrates a facile method to obtain OA conformations and highlights the potential of dimeric acceptors for high-performance PSCs.

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  • 26.
    Zhang, Chao
    et al.
    Uppsala University, Sweden.
    Cheng, Jun
    Xiamen University, China.
    Chen, Yiming
    Argonne National Laboratory, USA.
    Chan, Maria K. Y.
    Argonne National Laboratory, USA.
    Cai, Qiong
    University of Surrey, United Kingdom; The Faraday Institution, United Kingdom.
    Carvalho, Rodrigo P.
    Uppsala University, Sweden.
    Marchiori, Cleber
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Brandell, Daniel
    Uppsala University, Sweden.
    Araujo, Moyses
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Uppsala University, Sweden.
    Chen, Ming
    Huazhong University of Science and Technology, China.
    Ji, Xiangyu
    Huazhong University of Science and Technology, China.
    Feng, Guang
    Huazhong University of Science and Technology, China.
    Goloviznina, Kateryna
    Sorbonne Université, France.
    Serva, Alessandra
    Sorbonne Université, France.
    Salanne, Mathieu
    Sorbonne Université, France; Institut Universitaire de France, fRANCE.
    Mandai, Toshihiko
    National Institute for Materials Science, Japan.
    Hosaka, Tomooki
    Tokyo University of Science, Japan.
    Alhanash, Mirna
    Chalmers University of Technology, Sweden.
    Johansson, Patrik
    Chalmers University of Technology, Sweden; Alistore-ER, France.
    Qiu, Yun-Ze
    Tsinghua University, China.
    Xiao, Hai
    Tsinghua University, China.
    Eikerling, Michael
    Forschungszentrum Jülich GmbH and RWTH Aachen University, Germany.
    Jinnouchi, Ryosuke
    Toyota Central R&D Labs, Japan.
    Melander, Marko M.
    University of Jyväskylä, Finland.
    Kastlunger, Georg
    Technical University of Denmark, Denmark.
    Bouzid, Assil
    Institut de Recherche sur les Céramiques (IRCER), France.
    Pasquarello, Alfredo
    Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland.
    Shin, Seung-Jae
    Korea Advanced Institute of Science and Technology, South Korea; Yonsei University, South Korea.
    Kim, Minho M.
    Korea Advanced Institute of Science and Technology, South Korea.
    Kim, Hyungjun
    Korea Advanced Institute of Science and Technology, South Korea.
    Schwarz, Kathleen
    National Institute of Standards and Technology, USA.
    Sundararaman, Ravishankar
    Rensselaer Polytechnic Institute, USA.
    2023 Roadmap on molecular modelling of electrochemical energy materials2023In: Journal of Physics: Energy, E-ISSN 2515-7655, Vol. 5, no 4, article id 041501Article, review/survey (Refereed)
    Abstract [en]

    New materials for electrochemical energy storage and conversion are the key to the electrification and sustainable development of our modern societies. Molecular modelling based on the principles of quantum mechanics and statistical mechanics as well as empowered by machine learning techniques can help us to understand, control and design electrochemical energy materials at atomistic precision. Therefore, this roadmap, which is a collection of authoritative opinions, serves as a gateway for both the experts and the beginners to have a quick overview of the current status and corresponding challenges in molecular modelling of electrochemical energy materials for batteries, supercapacitors, CO2 reduction reaction, and fuel cell applications.

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