1. A novel multi-functional thiophene-based organic cation as passivation, crystalline orientation, and organic spacer agent for low-dimensional 3D/1D perovskite solar cellsAli Semerci, Ali Buyruk, Saim Emin, Rik Hooijer, Daniela Kovacheva, Peter Mayer, Manuel A. Reus, Dominic Blätte, Marcella Günther, Nicolai F. Hartmann, 2023, original scientific article Abstract: Recently, the mixed-dimensional (3D/2D or 3D/1D) perovskite solar cellsusing small organic spacers have attracted interest due to their outstandinglong-term stability. Here, a new type of thiophene-based organic cation2-(thiophene-2yl-)pyridine-1-ium iodide (ThPyI), which is used to fabricatemixed-dimensional 3D/1D perovskite solar cells, is presented. TheThPyI-based 1D perovskitoid is applied as a passivator on top of a 3D methylammonium lead iodide (MAPI) to fabricate surface-passivated 3D/1Dperovskite films or added alone into the 3D perovskite precursor to generatebulk-passivated 3D MAPI. The 1D perovskitoid acts as a passivating agent atthe grain boundaries of surface-passivated 3D/1D, which improves the powerconversion efficiency (PCE) of the solar cells. Grazing incidence wide-angleX-ray scattering (GIWAXS) studies confirm that ThPyI triggers the preferentialorientation of the bulk MAPI slabs, which is essential to enhance chargetransport. Champion bulk-passivated 3D and surface-passivated 3D/1Ddevices yield 14.10% and 19.60% PCE, respectively. The bulk-passivated 3Doffers favorable stability, with 84% PCE retained after 2000 h withoutencapsulation. This study brings a new perspective to the design of organicspacers having a different binding motif and a passivation strategy to mitigatethe impact of defects in hybrid 3D/1D perovskite solar cells.A. Semerci, A. Buyruk, R. Hooijer, P. Mayer, D. Blätte, M. Günther, T. Bein,T. AmeriDepartment of Chemistry and Center for NanoScience (CeNS)Ludwig-Maximilians-Universität MünchenButenandtstrasse 5–13 (E), 81377 Munich, GermanyE-mail:tayebeh.ameri@ed.ac.ukS.EminMaterialsResearchLaboratoryUniversityofNovaGoricaVipavska13c,Ajdovšˇcina5270,SloveniaThe ORCID identification number(s) for the author(s) of this articlecan be found under https://doi.org/10.1002/adom.202300267© 2023 The Authors. Advanced Optical Materials published byWiley-VCH GmbH. This is an open access article under the terms of theCreative Commons Attribution-NonCommercial License, which permitsuse, distribution and reproduction in any medium, provided the originalwork is properly cited and is not used for commercial purposes.DOI: 10.1002/adom.2023002671. IntroductionDuring the last decade, 3D organic–inorganic halide perovskites (OIHPs) haveemerged as promising absorber materialsfor photovoltaic applications due to theirsuperior properties such as high absorp-tion coefficient, long diffusion length ofthe charge carriers, fast charge transport,and tunable bandgap. The 3D OIHPs havedemonstrated rapid increase in powerconversion efficiency (PCE) from 3.8% to25.2%.[1–9]On the other hand, their mod-erate intrinsic stability against moistureand heat still has been a concern with aview on possible commercialization.[10–14]Instability of the 3D methyl ammoniumlead iodide (MAPI) perovskite is assumedto be due to its crystalline structure. Ionicmigration is now well recognized to affectthe photovoltaic properties of perovskitesolar cells. Especially, the ionic migrationcauses the generation and displacement ofvacancies in perovskite materials. OIHPsare mixed ionic–electronic conductors withiodide ions as the majority of ionic carriers.D. KovachevaInstitute of General and Inorganic ChemistryBulgarian Academy of SciencesSofia 1113, BulgariaM. A. Reus, P. Müller-BuschbaumTUM School of Natural SciencesDepartment of PhysicsChair for Functional MaterialsTechnical University of MunichJames-Franck-Str. 1, 85748 Garching, GermanyN. F. HartmannAttocube systems AGNanoscale AnalyticsneaspecEglfinger Weg 2, 85540 Haar, GermanyS. Lotfi, J. P. HofmannSurface Science LaboratoryDepartment of Materials and Earth SciencesTechnical University of DarmstadtOtto-Berndt-Str. 3, 64287 Darmstadt, GermanyAdv. Optical Mater.2023,11, 23002672300267 (1 of 13)© 2023 The Authors. Advanced Optical Materials published by Wiley-VCH GmbH
Keywords: perovskites, solar cells, passivation
Published in RUNG: 04.12.2023; Views: 432; Downloads: 2
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2. In vitro tumor hypoxia imaging with fluorescent covalent organic frameworksTina Skorjanc, Dinesh Shetty, Damjan Makuc, Gregor Mali, Martina Bergant Marušič, Matjaž Valant, 2023, published scientific conference contribution abstract Abstract: Hypoxia refers to a condition where cells and tissues experience low, inadequate levels of O2. While healthy tissues are typically supplied with sufficient O2 (normoxia), cancerous tissues commonly face hypoxia due to the tumor’s extraordinarily high demand for oxygen. Various fluorescent small-molecule probes have been designed for selective detection of hypoxia in living cells, but few nanomaterials have been investigated for this type of bioimaging. Herein, we prepare a fluorescent covalent organic framework (COF) with β-ketoenamine linkages and post-synthetically modify it to conjugate hypoxia-sensitive nitroimidazole moieties
into its pores (NI-COF). Stacks of sheets in NI-COF observed under electron microscopy were exfoliated by ultrasonication, and dynamic light scattering measurements confirmed particle size of less than 200 nm. Thus-prepared material exhibited good stability in physiological conditions and low cytotoxicity in in vitro experiments. NI-COF also showed useful fluorescence properties with an emission peak at 490 nm (λex = 420 nm) at both neutral and mildly acidic pH levels that are characteristic of tumor tissues. Encouraged by the favorable properties of the material, we incubated HeLa cells pre-treated in either hypoxic or normoxic conditions with NI-COF. Fluorescence microscopy images demonstrated that the material was preferentially taken up by hypoxic cells, which showed higher fluorescence signal in their interior than cells cultured under normoxia conditions. It is anticipated that this study will stimulate further developments of COFs for imaging various biological conditions.
Keywords: hypoxia, fluorescence, covalent organic frameworks, imaging, tumor cells
Published in RUNG: 19.09.2023; Views: 757; Downloads: 3
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3. The challenge with high permittivity acceptors in organic solar cells : a case study with Y-series derivativesPeter Fürk, Suman Mallick, Thomas Rath, Matiss Reinfelds, Mingjian Wu, Erdmann Spiecker, Nikola Simic, Georg Haberfehlner, Gerald Kothleitner, Barbara Ressel, 2023, original scientific article Abstract: Y-series acceptors have brought a paradigm shift in terms of power conversion efficiencies of organic solar cells in the last few years. Despite their high performance, these acceptors still exhibit substantial energy loss, stemming from their low-permittivity nature. To tackle the energy loss situation, we prepared modified Y-series acceptors with improved permittivities via an alternative synthetic route.
Keywords: solar cells, Y-series acceptors, morphology, efficiency measurements
Published in RUNG: 29.06.2023; Views: 1056; Downloads: 7
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4. Nitroreductase-sensitive fluorescent covalent organic framework for tumor hypoxia imaging in cellsTina Škorjanc, Dinesh Shetty, Sushil Kumar, Damjan Makuc, Gregor Mali, Janez Volavšek, Martina Bergant Marušič, Matjaž Valant, 2023, original scientific article Keywords: covalent organic frameworks, imaging, hypoxia, fluorescence, cancer cells
Published in RUNG: 17.05.2023; Views: 1028; Downloads: 10
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5. Nanoscopic roughness characterization of chitosan with buried graphene oxide for fuel cell applicationAhmed Kreta, Egon Pavlica, Mojca Božič, Gvido Bratina, 2023, published scientific conference contribution Keywords: AFM, chitosan, graphene oxide, fuel cells, membrane, roughness
Published in RUNG: 01.03.2023; Views: 1288; Downloads: 3
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6. Influence of P3HT:PCBM ratio on thermal and transport properties of bulk heterojunction solar cellsDorota Korte, Egon Pavlica, Domen Klančar, Gvido Bratina, Michal Pawlak, Ewa Gondek, Peng Song, Junyan Liu, B. Derkowska-Zielińska, 2023, original scientific article Keywords: organic bulk-heterojunction solar cells, polymer-fullerene solar cells, photothermal beam deflection spectrometry, non-radiative recombination, thermal diffusivity, frequency domain methods
Published in RUNG: 09.01.2023; Views: 1402; Downloads: 19
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7. Cationic Covalent Organic Polymer Thin Film for Label-free Electrochemical Bacterial Cell DetectionTina Skorjanc, Andraž Mavrič, Mads Nybo Sorensen, Gregor Mali, Changzhu Wu, Matjaž Valant, 2022, original scientific article Keywords: Bacteria, Electrical properties, Electrochemical cells, Electrodes, Sensors
Published in RUNG: 26.09.2022; Views: 1131; Downloads: 24
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8. Coevaporation of doped inorganic carrier-selective layers for high-performance inverted planar perovskite solar cellsJiexuan Jiang, Andraž Mavrič, Nadiia Pastukhova, Matjaž Valant, Qiugui Zeng, Zeyu Fan, Beibei Zhang, Yanbo Li, 2022, original scientific article Abstract: Inorganic carrier selective layers (CSLs), whose conductivity can be effectively tuned by doping, offer low-cost and stable alternatives for their organic counterparts in perovskite solar cells (PSCs). Herein, we employ a dual-source electron-beam co-evaporation method for the controlled deposition of copper-doped nickel oxide (Cu:NiO) and tungsten-doped niobium oxide (W:Nb2O5) as hole and electron transport layers, respectively. The mechanisms for the improved conductivity using dopants are investigated. Owing to the improved conductivity and optimized band alignment of the doped CSLs, the all-inorganic-CSLs-based PSCs achieves a maximum power conversion efficiency (PCE) of 20.47%. Furthermore, a thin titanium buffer layer is inserted between the W:Nb2O5 and the silver electrode to prevent the halide ingression and improve band alignment. This leads to a further improvement of PCE to 21.32% and a long-term stability (1200 h) after encapsulation. Finally, the large-scale applicability of the doped CSLs by co-evaporation is demonstrated for the device with 1 cm2 area showing a PCE of over 19%. Our results demonstrate the potential application of the co-evaporated CSLs with controlled doping in PSCs for commercialization.
Keywords: carrier selective layers, Cu-doped nickel oxide, electron-beam evaporation, perovskite solar cells, W-doped niobium oxide
Published in RUNG: 17.03.2022; Views: 1754; Downloads: 121
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9. In vitro toxicity of arsenic rich waters from an abandoned gold mine in northeast PortugalMaria do Rosário Costa, Doroteja Gošar, Marika Pinti, Adelaide Ferreira, Martina Bergant Marušič, 2021, original scientific article Keywords: arsenic, water contamination, cytotoxicity, genotoxicity, Caco-2 cells
Published in RUNG: 23.07.2021; Views: 1921; Downloads: 10
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10. A pyrrolopyridazinedione-based copolymer for fullerene-free organic solar cellsAstrid-Caroline Knall, Samuel Rabensteiner, Sebastian F. Hoefler, Matiss Reinfelds, Mathias Hobisch, Heike M. A. Ehmann, Nadiia Pastukhova, Egon Pavlica, Gvido Bratina, Illie Hanzu, Shuguang Wen, Renqiang Yang, Gregor Trimmel, Thomas Rath, 2021, original scientific article Abstract: The recent success of non-fullerene acceptors in organic photovoltaics also entails a change in the requirements to the polymer donor in terms of optical and morphological properties leading to a demand for novel conjugated polymers. Herein, we report on the synthesis of a 1,4-bis-(thiophene-2-yl)-pyrrolopyridazinedione based copolymer with 2-ethylhexyl substituents on the pyrrolopyridazinedione moiety. A 2D conjugated benzodithiophene (BDT) was chosen as comonomer. The resulting copolymer T-EHPPD-T-EHBDT showed a molecular weight of 10.2 kDa, an optical band gap of 1.79 eV, a hole mobility of 1.8 × 10−4 cm2 V−1 s−1 and a preferred face-on orientation with regard to the substrate. The comparably wide band gap as well as the determined energy levels (HOMO: −5.47 eV, LUMO: −3.68 eV) match well with the narrow band gap non-fullerene acceptor ITIC-F, which was used as the acceptor phase in the bulk heterojunction absorber layers in the investigated solar cells. The solar cells, prepared in inverted architecture, revealed power conversion efficiencies up to 7.4% using a donor:acceptor ratio of 1 : 1 in the absorber layer.
Keywords: non-fullerene solar cells, charge transport, charge mobility, power conversion efficiency
Published in RUNG: 27.01.2021; Views: 2537; Downloads: 0
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