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@article{faucris.307279260,
abstract = {Organic electronic devices (OEDs) are prone to oxygen- and water-induced degradation and therefore need to be encapsulated with barrier materials. In this work, an aerosol jet (AJ)-printing process is developed to coat perhydropolysilazane (PHPS) directly onto OEDs by adapting the print setup and systematically optimizing the process parameters. Furthermore, a novel curing process that converts PHPS to silica barrier layers is developed by combining damp heat (DH) exposure with subsequent vacuum–UV irradiation. This two-step treatment is shown to be considerably faster and gentler than the state-of-the-art curing processes and also yields a quantitatively higher conversion. Both the printing and the conversion process are fully compatible with OED devices, which is demonstrated by a damage-free direct encapsulation of organic solar cells. The encapsulated cells show a significant reduction of degradation in DH conditions (65 °C/85% r.h.), maintaining >95% of their initial performance for >100 h. Complementary electroluminescence measurements reveal that the AJ-printed barrier layers effectively prevent lateral water ingress into the devices. Herein, the proof of principle is provided that AJ printing can be used to print barrier layers directly onto OEDs and is thus an industrially highly relevant technology to precisely encapsulate such devices even on 3D objects.},
author = {Basu, Robin and Siah, Kok Siong and Distler, Andreas and Häußler, Felix and Franke, Jörg and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1002/adem.202300322},
faupublication = {yes},
journal = {Advanced Engineering Materials},
keywords = {aerosol jet printing; organic solar cells; perhydropolysilazane; printed barriers; solution-processed encapsulation},
note = {CRIS-Team Scopus Importer:2023-07-07},
peerreviewed = {Yes},
title = {{Aerosol}-{Jet}-{Printed} {Encapsulation} of {Organic} {Photovoltaics}},
year = {2023}
}
@article{faucris.220861120,
abstract = {Solution based thin film technology often implies challenging wetting behaviour which has to be improved in order to achieve good printing or coating qualities. A common way of solving such problems is the use of wetting agents but they often show undesired side effects. In this work, we introduce a generic strategy to overcome this problem. We demonstrate inkjet printed arrays of poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) dots to efficiently pin the three-phase contact line of wet films, thereby enforcing homogenous wetting and subsequent drying on low energetic surfaces. By printing and drying single droplets of ink, a matrix of anchoring points is created which pins the subsequently printed continuous wet layer and thus enables the coating of large surface areas with homogeneous, defect free films. This method also allows convenient patterning of surfaces by combining inkjet-printing of anchoring points with subsequent large area flood coating, e.g., by doctor blading. Furthermore, the defined placement of each anchoring point allows full thermodynamic control of the film formation by quantitative calculation of the processing windows and patterning precision. The beneficial application of this new strategy to printed electronics is demonstrated by fabricating organic solar cells with power conversion efficiencies of 5%. This is achieved by printing a hydrophilic PEDOT:PSS electron blocking layer without addition of surfactants at unprecedented quality onto an otherwise non-wettable hydrophobic active layer consisting of poly(3-hexylthiophene) (P3HT) and the indacenodithiophene-based non-fullerene acceptor O-IDTBR.},
author = {Maisch, Philipp and Eisenhofer, Lena M. and Tam, Kai Cheong and Distler, Andreas and Voigt, Monika M. and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1039/c9ta02209k},
faupublication = {yes},
journal = {Journal of Materials Chemistry A},
note = {CRIS-Team Scopus Importer:2019-06-18},
pages = {13215-13224},
peerreviewed = {Yes},
title = {{A} generic surfactant-free approach to overcome wetting limitations and its application to improve inkjet-printed {P3HT}:non-fullerene acceptor {PV}},
volume = {7},
year = {2019}
}
@article{faucris.214367071,
abstract = {Although green femtosecond lasers provide outstanding quality and wide processing
windows for monolithic interconnection of the individual cells in organic photovoltaic
(OPV) modules, they are hardly used in commercial applications, due to cost reasons.
In this work, a process has been developed that allows the monolithic interconnection
in OPV modules with an infrared sub‐nanosecond laser exclusively, without
compromising the performance of the modules. While the photoactive layer is
removed easily by green femtosecond pulses without damaging the bottom electrode,
this is not possible for infrared nanosecond pulses, due to their much larger optical
penetration length, which significantly exceeds the thickness of the active layer and
is well absorbed by the indium tin oxide (ITO) layer. This leads to damage of the
ITO bottom electrode, which in turn compromises the functionality of the module.
By systematically varying single‐pulse laser fluence and spatial pulse overlap, the laser
parameters are optimized in such a way that the contact area between the residues of
the metal oxide bottom electrode and the silver nanowire top electrode is maximized
so that the electrical resistances of the contacts are sufficiently small not to affect
device performance. This is demonstrated by presenting large‐area OPV modules
based on the well‐characterized reference system P3HT:PCBM that show efficiencies
of up to 2.4%. This achievement opens up the way towards reliable roll‐to‐roll
(R2R) laser patterning processes with sub‐nanosecond lasers and thus represents a
breakthrough with respect to cost‐effective R2R manufacturing of OPV modules,
due to grossly reduced investment and maintenance costs for laser sources.
F) that are 10–15% higher than those of the m-Si modules at 45° inclination. For vertical (90°) mounting, the YF of the OPV modules is even 24–30% higher than that of their inorganic counterparts, thus making them ideally suited for façade integrated BIPV. Laboratory investigations reveal that the superior performance of OPV modules in the vertical position is mainly due to a strongly enhanced fill factor (FF) at reduced in-plane irradiance. At a 45° inclination, the positive temperature coefficient of the OPV modules also plays an important role during high-irradiance hours.},
author = {Feroze, Sarmad and Distler, Andreas and Forberich, Karen and Ahmed Channa, Iftikhar and Doll, Bernd and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1016/j.solener.2023.111894},
faupublication = {yes},
journal = {Solar Energy},
keywords = {Building-integrated photovoltaics; Energy harvest; Organic photovoltaics; Outdoor monitoring},
note = {CRIS-Team Scopus Importer:2023-09-22},
peerreviewed = {Yes},
title = {{Comparative} analysis of outdoor energy harvest of organic and silicon solar modules for applications in {BIPV} systems},
volume = {263},
year = {2023}
}
@article{faucris.313783726,
abstract = {Commercialization of printed photovoltaics requires knowledge of the optimal composition and microstructure of the single layers, and the ability to control these properties over large areas under industrial conditions. While microstructure optimization can be readily achieved by lab scale methods, the transfer from laboratory scale to a pilot production line (“lab to fab”) is a slow and cumbersome process: first, the difficulty of operating structure-sensitive methods in-line impedes proper microstructure characterization, and second, the processing-functionality relationship must be redetermined for every material combination as the results obtained by typical lab-scale spin-coating cannot be directly transferred to other coating methods. Here, we show how we can optimize the performance of organic solar cells and at the same time assess process performance in a 2D combinatorial approach directly on an industrially relevant slot die coating line. This is enabled by a multi-nozzle slot die coating head allowing parameter variations along and across the web. This modification allows us to generate and analyze 3750 devices in a single coating run, varying the active layer donor : acceptor ratio and the thickness of the electron transport layer (ETL). We use Gaussian Process Regression (GPR) to exploit the whole dataset for precise determination of the optimal parameter combination. Performance-relevant features of the active layer morphology are inferred from UV-Vis absorption spectra. By mapping morphology in this way, small undesired gradients of process conditions (extrusion rates, annealing temperatures) are detected and their effect on device performance is quantified. The correlation between process parameters, morphology and performance obtained by GPR provides hints to the underlying physics, which are finally quantified by automated high-throughput drift-diffusion simulations. This leads to the conclusion that voltage losses which are observed for very thin ETL coatings are due to incomplete coverage of the electrode by the ETL, which causes enhanced surface recombination.},
author = {Wagner, Michael and Distler, Andreas and Le Corre, Vincent Marc and Zapf, Simon and Baydar, Burak and Schmidt, Hans-Dieter and Heyder, Madeleine and Forberich, Karen and Lüer, Larry and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1039/d3ee01801f},
faupublication = {yes},
journal = {Energy and Environmental Science},
note = {CRIS-Team Scopus Importer:2023-11-10},
peerreviewed = {Yes},
title = {{Cutting} “lab-to-fab” short: high throughput optimization and process assessment in roll-to-roll slot die coating of printed photovoltaics},
year = {2023}
}
@article{faucris.277559308,
abstract = {Solar cells transparent in the visible range are highly requested for integration in see-through photovoltaic (PV) applications such as building glass façades or greenhouse roofs. The development of advanced transparent PV can fully exploit the tandem technology where the top cell absorbs the near-ultraviolet solar spectrum while the bottom one absorbs the near-infrared part. Herein, a possible implementation of this tandem PV paradigm, namely, the tandem structure composed of a high-bandgap halide perovskite solar cell and a low-bandgap organic solar cell, is considered. Electro-optical simulation results based on parameters calibrated on experimental data show that an efficiency of 15% can be achieved with an average visible transmittance above 50%. This can be obtained considering the halide perovskite with mixed chlorine and bromine anions, a nonfullerene-based bulk heterojunction, a well-calibrated light management, and a three-terminal configuration of the tandem.},
author = {Rossi, Daniele and Forberich, Karen and Matteocci, Fabio and Der Maur, Matthias Auf and Egelhaaf, Hans-Joachim and Brabec, Christoph and Di Carlo, Aldo},
doi = {10.1002/solr.202200242},
faupublication = {yes},
journal = {Solar RRL},
keywords = {organic solar cells; pervoskite solar cells; solar cell simulations; tandem perovskite/organic solar cells; transparent solar cells},
note = {CRIS-Team Scopus Importer:2022-07-08},
peerreviewed = {Yes},
title = {{Design} of {Highly} {Efficient} {Semitransparent} {Perovskite}/{Organic} {Tandem} {Solar} {Cells}},
year = {2022}
}
@article{faucris.309438438,
abstract = {Printable planar carbon electrodes emerge as a promising replacement for thermally evaporated metals as the rear contact for perovskite solar cells (PSCs). However, the power conversion efficiencies (PCEs) of the state-of-the-art carbon-electrode PSC (c-PSC) noticeably lag behind their metal-electrode counterparts. Here, we propose a hole-transporting bilayer (HTbL) configuration to improve the fill factor and the open-circuit voltage of c-PSCs simultaneously. The HTbL is prepared by sequentially blade coating two organic semiconductors between perovskite and carbon, with the outer HTL enhancing hole extraction to carbon, while the inner HTL mitigates perovskite surface recombination. Consequently, our fully printed c-PSCs with HTbL outperform those with single HTL, and a stabilized champion PCE of 19.2% is achieved compared with that of 17.3%. Our prototype c-PSC stably operates during 1 sun, 65°C aging test (ISOS-L-2I) for 2,500 h showing negligible PCE drop, validating its potential as a highly cost-effective photovoltaic technology.},
author = {Du, Tian and Qiu, Shudi and Zhou, Xin and Le Corre, Vincent Marc and Wu, Mingjian and Dong, Lirong and Peng, Zijian and Zhao, Yicheng and Jang, Dongju and Spiecker, Erdmann and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1016/j.joule.2023.06.005},
faupublication = {yes},
journal = {Joule},
keywords = {bilayer; carbon electrode; fully printed perovskite solar cells; hole transporting; stability},
note = {CRIS-Team Scopus Importer:2023-08-18},
peerreviewed = {Yes},
title = {{Efficient}, stable, and fully printed carbon-electrode perovskite solar cells enabled by hole-transporting bilayers},
year = {2023}
}
@article{faucris.262122376,
abstract = {In dem vom Bundesministerium für Wirtschaft und Energie (BMWi) geförderten Projekt „Fassade3“ entwickelt ein Konsortium aus akademischen und industriellen Partnern ein multifunktionales Fassadenelement mit integrierter organischer Photovoltaik (OPV). Die Fassade kann aufgrund ihrer modularen Struktur vorgefertigt und sowohl in Neu- als auch Bestandsgebäude integriert werden. Sie fungiert als Energiequelle, dient der thermischen Isolation, bietet Sonnenschutz für den Innenraum und optimiert so die Energieeffizienz des Gebäudes. Mit einfachen Mitteln lässt sich somit eine voll funktionsfähige und gleichzeitig ästhetisch ansprechende Konstruktion realisieren. Ein eigens entwickeltes Messsystem erlaubt die Echtzeit-Überwachung der Energiebilanz der Fassade. Erste Ergebnisse zum Leistungsverhältnis der OPV-Module sind vielversprechend.},
author = {Egelhaaf, Hans-Joachim and Brabec, Christoph and Neberich, Marcel and Senguttuvan, Kaushik and Hoga, Felix and Kießling, Günther and Braun, Matthias and Bordin, Susanna and Wagner, Michael and Distler, Andreas and Feroze, Sarmad and Dentel, Arno},
doi = {10.37544/1618-193X-2021-7-8-16},
faupublication = {yes},
journal = {BWK Das Energie Fachmagazin},
pages = {16-21},
peerreviewed = {Yes},
title = {{Fassadenelemente} mit organischer {Photovoltaik}},
volume = {73},
year = {2021}
}
@article{faucris.310778536,
abstract = {While the power conversion efficiency (PCE) of organic photovoltaics (OPV) on small-area lab cells has rapidly increased during the last few years, the performance on module level and the availability of OPV modules on the market is still limited, primarily due to specific constraints imposed by the industrial production process. This work deals with the upscaling process of latest-generation OPV from small-area lab cells to fully solution-processed modules, which are compatible to industrial roll-to-roll (R2R) printing. This transfer is demonstrated step by step from material selection and process optimization for every single layer of the stack (photoactive layer, charge transporting layers, and solution-processed top electrode)–including long-term stability investigations (thermal and light)–to scaling up the device area by a factor of >100. Thus, a semitransparent OPV module with 10.8% PCE on 10.2 cm2 active area is achieved, which is among the highest performances for semitransparent, fully solution-processed OPV modules. The individual developments all meet the requirements for industrial R2R printing (green solvents, processing in air, annealing ≤140 °C, etc.), which ensures that both the optimized layer stack and the fabrication process are fully scalable and easily transferable to large-scale production.},
author = {Wachsmuth, Josua and Distler, Andreas and Liu, Chao and Heumüller, Thomas and Liu, Yang and Aitchison, Catherine M. and Hauser, Alina and Rossier, Michael and Robitaille, Amélie and Llobel, Marc Antoine and Morin, Pierre Olivier and Thepaut, Anaïs and Arrive, Charline and McCulloch, Iain and Zhou, Yinhua and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1002/solr.202300602},
faupublication = {yes},
journal = {Solar RRL},
keywords = {ambient air; organic photovoltaics (OPVs); roll-to-roll (R2R)-compatibility; semitransparent modules; solution-processing; upscaling},
note = {CRIS-Team Scopus Importer:2023-09-22},
peerreviewed = {Yes},
title = {{Fully} {Printed} and {Industrially} {Scalable} {Semitransparent} {Organic} {Photovoltaic} {Modules}: {Navigating} through {Material} and {Processing} {Constraints}},
year = {2023}
}
@article{faucris.213943024,
abstract = {Colloidal nanocrystals from PbS are successfully applied in highly sensitive infrared photodetectors with various device architectures. Here, we demonstrate all-printed devices with high detectivity (similar to 10(12) cm Hz(1/2) /W) and a cut-off frequency of >3 kHz. The low material consumption (<0.3 mg per detector) and short processing time (14 s per detector) enabled by the automated printing promises extremely low device costs. To enable all-printed devices, an ink formulation was developed based on nanocrystals stabilized by perovskite-like methylammonium iodobismuthate ligands, which are dispersed in a ternary solvent. Fully inkjet printed devices based on this solvent were achieved with printed silver electrodes and a ZnO interlayer. Considerable improvements were obtained by the addition of small amounts of the polymer poly(vinylpyrrolidone) to the ink. The polymer improved the colloidal stability of the ink and its film-formation properties and thus enabled the scalable printing of single detectors and detector arrays. While photoconductors were shown here, the developed ink will certainly find application in a series of further electronic devices based on nanocrystals from a broad range of materials.},
author = {Yousefiamin, Amirabbas and Killilea, Niall Andrew and Sytnyk, Mykhailo and Maisch, Philipp and Tam, Kwok-Kan and Egelhaaf, Hans-Joachim and Langner, Stefan and Stubhan, Tobias and Brabec, Christoph and Rejek, Tobias and Halik, Marcus and Poulsen, Katharina and Niehaus, Jan and Koeck, Anton and Heiß, Wolfgang},
doi = {10.1021/acsnano.8b09223},
faupublication = {yes},
journal = {ACS nano},
keywords = {colloidal nanocrystals; infrared detectors; inkjet printing; PbS; solution processing},
pages = {2389-2397},
peerreviewed = {Yes},
title = {{Fully} {Printed} {Infrared} {Photodetectors} from {PbS} {Nanocrystals} with {Perovskite} {Ligands}},
volume = {13},
year = {2019}
}
@article{faucris.267631655,
abstract = {One of the advantages of organic photovoltaics (OPV) over other contemporary technologies is its relative ease of processing. There are, however, very few works that have realized fully printed devices, including the bottom electrode, let alone with a scalable process in a reasonable device size (>1 cm(2)). In this work, design steps and optimization processes towards fully printed OPV modules with scalable processes are demonstrated for the first time. An overview on issues related to upscaling with printed electrodes is first provided. The various issues are then addressed by a rational design process supported by measurements and calculations. Finally, a set of fully printed OPV modules are fabricated using these optimized parameters that have over 3.5-cm(2) active area with 5% efficiency. For the first time, this work has also demonstrated the process compatibility of fully printed device structures with non-fullerene acceptor systems, which enables more design opportunities for the current generation of high-performance OPV materials.},
author = {Tam, Kai Cheong and Kubis, Peter and Maisch, Philipp and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1002/pip.3521},
faupublication = {yes},
journal = {Progress in Photovoltaics},
note = {CRIS-Team WoS Importer:2021-12-31},
peerreviewed = {Yes},
title = {{Fully} printed organic solar modules with bottom and top silver nanowire electrodes},
year = {2021}
}
@article{faucris.274944005,
abstract = {Organic photovoltaic (OPV) devices have the potential to be superior to other PV technologies for the use in applications that require very high flexibility or maximum specific power (power-per-weight ratio), such as textile integration, wearable electronics, or outer space applications. However, OPV devices also require encapsulation by barrier films to reduce the degradation driven by extrinsic factors, which in turn limits their flexibility and leads to lower specific power values. In this work, fully solution-processed (including both electrodes) semitransparent organic solar cells (OSCs) with performance comparable with conventional indium tin oxide-based devices are processed directly onto different barrier films of varying thicknesses. Direct cell fabrication onto barrier films leads to the elimination of the additional polyethylene terephthalate substrate and one of the two adhesive layers in the final stack of an encapsulated OPV device by replacing the industrial state-of-the-art sandwich encapsulation with a top-only encapsulation process, which yields significantly thinner and lighter 'product-relevant' PV devices. In addition to the increase of the specific power to 0.38 W g(-1), which is more than four times higher than sandwich-encapsulated devices, these novel OSCs exhibit better flexibility and survive 5000 bending cycles with 4.5 mm bending radius. Moreover, the devices show comparable stability as conventionally encapsulated devices under constant illumination (1 sun) in ambient air for 1000 h. Finally, degradation under damp heat conditions (65 degrees C, 85% rh) was investigated and found to be determined by a combination of different factors, namely (UV) light soaking, intrinsic barrier properties, and potential damaging of the barriers during (laser) processing.},
author = {Güler, Ezgi and Distler, Andreas and Basu, Robin and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1088/2058-8585/ac66ae},
faupublication = {yes},
journal = {Flexible and Printed Electronics},
keywords = {solution-processability; specific power; organic photovoltaics; silver nanowire; transparent electrodes; flexible electronics; barrier films},
note = {CRIS-Team WoS Importer:2022-05-13},
peerreviewed = {Yes},
title = {{Fully} solution-processed, light-weight, and ultraflexible organic solar cells},
volume = {7},
year = {2022}
}
@article{faucris.243317778,
abstract = {Manufacturing commercially viable perovskite solar cells still requires appropriate low-temperature and scalable deposition processes to be developed. While α-phase FAPbI3 has higher thermal stability and broader absorption than MAPbI3, there still is no report of a pure α-phase FAPbI3 perovskite film obtained by a scalable printing method. Moreover, spontaneous conversion of the α-phase to non-perovskite δ-phase under ambient conditions poses a serious challenge for practical applications. Herein, a scalable and fully solution based printing method for the fabrication of pure α-phase FAPbI3 perovskite solar cells is reported. Through adding N-methyl pyrrolidone and methylammonium chloride to the dimethylformamide based precursor solution to control the crystallization, and vacuum or air-flow assisted film drying, pure α-FAPbI3 phase is obtained by doctor blading. The resulting α-FAPbI3 film is highly stable, with no δ-FAPbI3 phase being formed even after keeping it in an ambient atmosphere over a period of 200 days without encapsulation. In addition, a fully solution processed PSC with a PCE of 16.1% is processed by the vacuum assisted method, and 17.8% by the air-flow assisted method. Replacing silver with a printed carbon electrode provides a stable PCE up to 15% for the vacuum assisted and 16.4% for the air-flow assisted method, which is the highest performance of FAPbI3 solar cells to date. Compared with MAPbI3, the fully printed FAPbI3 perovskite devices exhibit a remarkable thermal stability in humid atmospheres which makes them a promising candidate for scalable production and commercialization.},
author = {Yang, Fu and Dong, Lirong and Jang, Dongju and Tam, Kai Cheong and Zhang, Kaicheng and Li, Ning and Guo, Fei and Li, Cong and Arrive, Charline and Bertrand, Mélanie and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1002/aenm.202001869},
faupublication = {yes},
journal = {Advanced Energy Materials},
keywords = {carbon electrodes; doctor blades; fully printed devices; long-term stability; α-FAPbI},
note = {CRIS-Team Scopus Importer:2020-10-02},
peerreviewed = {Yes},
title = {{Fully} {Solution} {Processed} {Pure} α-{Phase} {Formamidinium} {Lead} {Iodide} {Perovskite} {Solar} {Cells} for {Scalable} {Production} in {Ambient} {Condition}},
year = {2020}
}
@article{faucris.106800144,
abstract = {The first oligomerisation of phenyl-C-butyric acid methyl ester (PCBM) using a facile atom transfer radical addition polymerization (ATRAP) and its exploitation for organic photovoltaic devices is described. Oligo{(phenyl-C-butyric acid methyl ester)-alt-[1,4-bis(bromomethyl)-2,5-bis(octyloxy)benzene]} (OPCBMMB) shows opto-electronic properties equivalent to those of PCBM but has a higher glass transition temperature. When mixed with various band gap semiconducting polymers, OPCBMMB delivers performances similar to PCBM but with an enhanced stabilization of the bulk heterojunction in photovoltaic devices on plastic substrates under thermal stress, regardless of the degree of crystallinity of the polymer and without changing opto-electronic propertie},
author = {Ramanitra, Hasina H. and Dowland, Simon A. and Bregadiolli, Bruna A. and Salvador, Michael and Silva, Hugo Santos and Begue, Didier and Graeff, Carlos F. O. and Peisert, Heiko and Chasse, Thomas and Rajoelson, Sambatra and Osvet, Andres and Brabec, Christoph and Egelhaaf, Hans-Joachim and Morse, Graham E. and Distler, Andreas and Hiorns, Roger C.},
doi = {10.1039/c6tc03290g},
faupublication = {yes},
journal = {Journal of Materials Chemistry C},
keywords = {Engineering controlled terms: Atom transfer radical polymerization; Electronic properties; Energy gap; Esters; Free radical reactions; Glass transition; Heterojunctions; Oligomers; Photoelectrochemical cells; Photovoltaic cells; Semiconducting polymers; Stabilization; Substrates Atom transfer radical addition; Bulk heterojunction; Degree of crystallinity; Optoelectronic properties; Organic photovoltaic devices; Photovoltaic devices; Polymer photovoltaic cells; Thermal stabilization Engineering main heading: Butyric acid},
pages = {8121-8129},
peerreviewed = {Yes},
title = {{Increased} thermal stabilization of polymer photovoltaic cells with oligomeric {PCBM}},
volume = {4},
year = {2016}
}
@article{faucris.213950918,
abstract = {Water ingress into the encapsulation of electronic devices is a serious issue, especially for organic and perovskite-based electronics. In order to guide the development of suitable barrier materials and design, a reliable, fast, and non-destructive analysis tool is required. In this work, an imaging setup is presented, which is based on selective infrared (IR) radiation sources and a mid-IR sensitive camera that uses the absorption hand of water around 1920 nm and a reference band. This system enables us to monitor the distribution of water concentration inside the packaging of devices and its change over time. Our measurement is capable of detecting the local presence of water down to the mg/m(2) concentration range in a wide variety of encapsulation materials. The new tool allows identifying the pathways of moisture ingress into the encapsulation along with the corresponding diffusion coefficient. Thus, it provides fast and reliable analysis of humidity related failure mechanisms, and consequently helps to improve the design of encapsulation materials and processes.},
author = {Hepp, Johannes and Vetter, Andreas and Langner, Stefan and Woiton, Michael and Jovicic, Gordana and Burlafinger, Klaus and Hauch, Jens and Camus, Christian and Egelhaaf, Hans-Joachim and Brabec, Christoph},
doi = {10.1109/JPHOTOV.2018.2877883},
faupublication = {yes},
journal = {IEEE Journal of Photovoltaics},
keywords = {Degradation; diffusion processes; optical signal detection; organic photovoltaics (PVs); packaging},
pages = {252-258},
peerreviewed = {Yes},
title = {{Infrared} {Absorption} {Imaging} of {Water} {Ingress} {Into} the {Encapsulation} of ({Opto}-){Electronic} {Devices}},
volume = {9},
year = {2019}
}
@incollection{faucris.246639908,
abstract = {This chapter provides a review on digital printing of organic solar cells (OSCs) and perovskite solar cells (PSCs). It starts with a brief introduction to the fundamentals of both solar technologies. Highlighting the specific demands of many novel solar applications, the necessity to fabricate devices using cheap and most versatile techniques, such as drop-on-demand inkjet, is outlined. A short discussion on the fundamentals of inkjet technology provides the background for a literature overview on digitally printed OSCs and PSCs. The main part of this chapter describes the most significant achievements in the field and remaining challenges for inkjet fabrication of active layers, electron- as well as hole-transport layers and electrodes. An outlook on the perspectives that the combination of printed photovoltaics and inkjet has to offer concludes the chapter.
2 and 11.7% on a module area of 204 cm2. The decisive developments leading to this achievement include the optimization of the module layout as well as the high-resolution short-pulse (nanosecond) laser structuring processes involved in the manufacturing of such modules. By minimizing the inactive areas within the total module area that are used for interconnecting the individual solar cells of the module in series, geometric fill factors of over 95% have been achieved. A production yield of 100% working modules during the manufacturing of these modules and an extremely narrow distribution of the final PCE values underline the excellent process control and reproducibility of the results. The new developments and their implementation into the production process of the record OPV modules are described in detail, along with the challenges that arose during this development. Finally, dark lock-in thermography (DLIT), electroluminescence (EL), and photoluminescence (PL) measurements of the record module are presented.},
author = {Distler, Andreas and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1002/pip.3336},
faupublication = {yes},
journal = {Progress in Photovoltaics},
keywords = {certified power conversion efficiency (PCE); laser patterning; organic photovoltaics (OPV); solar modules; world record},
note = {CRIS-Team Scopus Importer:2020-09-25},
peerreviewed = {unknown},
title = {{Organic} photovoltaic modules with new world record efficiencies},
year = {2020}
}
@article{faucris.304463951,
abstract = {Unencapsulated organic solar cells are prone to severe performance losses in the presence of moisture. Accelerated damp heat (85 °C/85% RH) studies are presented and it is shown that the hygroscopic hole-transporting PEDOT:PSS layer is the origin of device failure in the case of prototypical inverted solar cells. Complementary measurements unveil that under these conditions a decreased PEDOT:PSS work function along with areas of reduced electrical contact between active layer and hole-transport layer are the main factors for device degradation rather than a chemical reaction of water with the active layer. Replacements for PEDOT:PSS are explored and it is found that tungsten oxide (WO3) or phosphomolybdic acid (PMA)—materials that can be processed from benign solvents at room temperature—yields comparable performance as PEDOT:PSS and enhances the resilience of solar cells under damp heat. The stability trend follows the order PEDOT:PSS << WO3 < PMA, with PEDOT:PSS-based devices failing after few minutes, while PMA-based devices remain nearly pristine over several hours. PMA is thus proposed as a robust, solution-processable hole extraction layer that can act as a one to one replacement of PEDOT:PSS to achieve organic solar cells with significantly improved longevity.},
author = {Wachsmuth, Josua and Distler, Andreas and Deribew, Dargie and Salvador, Michael Filipe and Brabec, Christoph and Egelhaaf, Hans-Joachim},
doi = {10.1002/adem.202300595},
faupublication = {yes},
journal = {Advanced Engineering Materials},
keywords = {degradation and stability; humidity; organic photovoltaics; phosphomolybdic acid; solution processed},
note = {CRIS-Team Scopus Importer:2023-06-02},
peerreviewed = {Yes},
title = {{Overcoming} {Moisture}-{Induced} {Degradation} in {Organic} {Solar} {Cells}},
year = {2023}
}
@article{faucris.267484439,
abstract = {In solution processing of thin films, the material layer is deposited from a solution composed of several solutes and solvents. The final morphology and hence the properties of the film often depend on the time needed for the evaporation of the solvents. This is typically the case for organic photoactive or electronic layers. Therefore, it is important to be able to predict the evaporation kinetics of such mixtures. We propose here a new phase-field model for the simulation of evaporating fluid mixtures and simulate their evaporation kinetics. Similar to the Hertz-Knudsen theory, the local liquid-vapor (LV) equilibrium is assumed to be reached at the film surface and evaporation is driven by diffusion away from this gas layer. In the situation where the evaporation is purely driven by the LV equilibrium, the simulations match the behavior expected theoretically from the free energy: for evaporation of pure solvents, the evaporation rate is constant and proportional to the vapor pressure. For mixtures, the evaporation rate is in general strongly time-dependent because of the changing composition of the film. Nevertheless, for highly nonideal mixtures, such as poorly compatible fluids or polymer solutions, the evaporation rate becomes almost constant in the limit of low Biot numbers. The results of the simulation have been successfully compared to experiments on a polystyrene-toluene mixture. The model allows to take into account deformations of the liquid-vapor interface and, therefore, to simulate film roughness or dewetting.},
author = {Ronsin, Olivier and Jang, Dong Ju and Egelhaaf, Hans-Joachim and Brabec, Christoph and Harting, Jens},
doi = {10.1021/acsami.1c12079},
faupublication = {yes},
journal = {ACS Applied Materials and Interfaces},
keywords = {evaporation; film drying; liquid-vapor equilibrium; phase-field},
note = {CRIS-Team Scopus Importer:2021-12-24},
pages = {55988-56003},
peerreviewed = {Yes},
title = {{Phase}-{Field} {Simulation} of {Liquid}-{Vapor} {Equilibrium} and {Evaporation} of {Fluid} {Mixtures}},
volume = {13},
year = {2021}
}
@article{faucris.309435706,
abstract = {To achieve maximum efficiency in organic photovoltaics (OPV), functional layers with uniform and exactly predefined thickness are required. An in-depth understanding of the coating process is therefore crucial for an accurate process control. In this paper, the meniscus-guided blade coating process, which is the most commonly used process for the manufacturing of organic electronics, is investigated by experimental and numerical methods. A computational fluid dynamics (CFD) model is created to simulate the coating behaviour of P3HT:O IDTBR, an industrial state-of-the-art active material system used in OPV, and its results' independence of numerical parameters is ensured. In particular, the influence of the coating velocity and the initially injected fluid volume on the resulting wet film thickness is studied. The developed CFD analysis is able to reproduce the experimental results with very high accuracy. It is found that the film thickness follows a power law dependence on the velocity (˜v 2/3) and a linear dependence on the ink volume (˜V). Accordingly, an analytical expression based on our theoretical considerations is presented, which predicts the wet film thickness as a function of the coating velocity and the ink volume only based on easily accessible ink properties. Consequently, this CFD model can effectively substitute time-consuming and expensive experiments, which currently have to be performed manually in the laboratory for a multitude of novel material systems, and thus supports highly accelerated material research. Moreover, the results of this work can be used to achieve homogeneous large-area coatings by utilising accelerated blade coating.},
author = {Gumpert, Fabian and Janßen, Annika and Brabec, Christoph and Egelhaaf, Hans-Joachim and Lohbreier, Jan and Distler, Andreas},
doi = {10.1080/19942060.2023.2242455},
faupublication = {yes},
journal = {Engineering Applications of Computational Fluid Mechanics},
keywords = {coating techniques; COMSOL multiphysics; Numerical simulation; organic photovoltaics; renewable energy; thin films},
note = {CRIS-Team Scopus Importer:2023-08-18},
peerreviewed = {Yes},
title = {{Predicting} layer thicknesses by numerical simulation for meniscus-guided coating of organic photovoltaics},
volume = {17},
year = {2023}
}
@article{faucris.240324841,
abstract = {Halide perovskites are one of the ideal photovoltaic materials for constructing flexible solar devices due to relatively high efficiencies for low-temperature solution-processed devices. However, the overwhelming majority of flexible perovskite solar cells are produced using spin coating, which represents a major hurdle for upscaling. Here, a scalable approach is reported to fabricate efficient and robust flexible perovskite solar cells on a polymer substrate. Thiourea is introduced into perovskite precursor solution to modulate the crystal growth, resulting in dense and uniform perovskite thin films on rough surfaces. As a decisive step, a cascade energy alignment is realized for the hole extraction layer by rationally designing a bilayer interface comprised of PEDOT:PSS/PTAA with a distinct offset in the highest occupied molecular orbital levels, enabling markedly enhanced charge extraction and spectral response. An efficiency as high as 19.41% and a record fill factor up to 81% are achieved for flexible perovskite devices processed by a scalable printing method. Equally important, the bilayer interface reinforces the bendability of the indium tin oxide substrate, leading to enhanced mechanical robustness of the flexible devices. These results underpin the importance of morphology control and interface design in constructing high-performance flexible perovskite solar cells.},
author = {Wang, Zhen and Zeng, Linxiang and Zhang, Cuiling and Lu, Yuanlin and Qiu, Shudi and Wang, Chuan and Liu, Chong and Pan, Lijun and Wu, Shaohang and Hu, Jinlong and Liang, Guangxing and Fan, Ping and Egelhaaf, Hans-Joachim and Brabec, Christoph and Guo, Fei and Mai, Yaohua},
doi = {10.1002/adfm.202001240},
faupublication = {yes},
journal = {Advanced Functional Materials},
keywords = {bilayer interface; blade coating; cascade energy alignment; flexible solar cells; perovskite},
note = {CRIS-Team Scopus Importer:2020-07-10},
peerreviewed = {Yes},
title = {{Rational} {Interface} {Design} and {Morphology} {Control} for {Blade}-{Coating} {Efficient} {Flexible} {Perovskite} {Solar} {Cells} with a {Record} {Fill} {Factor} of 81%},
year = {2020}
}
@article{faucris.280971207,
abstract = {Organic photovoltaics (OPVs) have progressed steadily through three stages of photoactive materials development: (i) use of poly(3-hexylthiophene) and fullerene-based acceptors (FAs) for optimizing bulk heterojunctions; (ii) development of new donors to better match with FAs; (iii) development of non-fullerene acceptors (NFAs). The development and application of NFAs with an A-D-A configuration (where A = acceptor and D = donor) has enabled devices to have efficient charge generation and small energy losses (Eloss < 0.6 eV), resulting in substantially higher power conversion efficiencies (PCEs) than FA-based devices. The discovery of Y6-type acceptors (Y6 = 2,2'-((2Z,2'Z)-((12,13-bis (2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]-thiadiazolo [3,4-e]-thieno- [2 ",3 ":4',5']thieno-[2',3':4,5]pyrrolo-[3,2-g]thieno-[2',3':4,5]thieno-[3,2-b]indole-2,10- diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))-dimalononitrile) with an A-DA' D-A configuration has further propelled the PCEs to go beyond 15% due to smaller Eloss values (& SIM;0.5 eV) and higher external quantum efficiencies. Subsequently, the PCEs of Y6-series single-junction devices have increased to > 19% and may soon approach 20%. This review provides an update of recent progress of OPV in the following aspects: developments of novel NFAs and donors, understanding of the structure-property relationships and underlying mechanisms of state-of-the-art OPVs, and tasks underpinning the commercialization of OPVs, such as device stability, module development, potential applications, and high-throughput manufacturing. Finally, an outlook and prospects section summarizes the remaining challenges for the further development of OPV technology.},
author = {Zhang, Guichuan and Lin, Francis R. and Qi, Feng and Heumüller, Thomas and Distler, Andreas and Egelhaaf, Hans-Joachim and Li, Ning and Chow, Philip C. Y. and Brabec, Christoph and Jen, Alex K. -Y. and Yip, Hin-Lap},
doi = {10.1021/acs.chemrev.1c00955},
faupublication = {yes},
journal = {Chemical Reviews},
note = {CRIS-Team WoS Importer:2022-08-26},
peerreviewed = {Yes},
title = {{Renewed} {Prospects} for {Organic} {Photovoltaics}},
year = {2022}
}
@article{faucris.204906461,
abstract = {Thin-film solar cells based on hybrid organo-halide lead perovskites achieve
over 22% power conversion efficiency (PCE). A photovoltaic technology at
such high performance is no longer limited by efficiency. Instead, lifetime and
reliability become the decisive criteria for commercialization. This requires a
standardized and scalable architecture which does fulfill all requirements for
larger area solution processing. One of the most highly demanded technologies
is a low temperature and printable conductive ink to substitute evaporated
metal electrodes for the top contact. Importantly, that electrode technology
must have higher environmental stability than, for instance, an evaporated
silver (Ag) electrode. Herein, planar and entirely low-temperature-processed
perovskite devices with a printed carbon top electrode are demonstrated. The
carbon electrode shows superior photostability compared to reference devices
with an evaporated Ag top electrode. As hole transport material, poly (3′hexyl
thiophene) (P3HT) and copper(I) thiocyanate (CuSCN), two cost-effective
and commercially available p-type semiconductors are identified to effectively
replace the costlier 2,2′,7,7′-Tetrakis-(N,N-di-4-methoxyphenylamino)-
9,9′-spirobifluorene (spiro-MeOTAD). While methylammonium lead iodide
(MAPbI3)-based perovskite solar cells (PSCs) with an evaporated Ag electrode
degrade within 100 h under simulated sunlight (AM 1.5), fully solution-processed
PSCs with printed carbon electrodes preserve more than 80% of their
initial PCE after 1000 h of constant illumination.
finite element (FEM) simulation rationalizes the excellent electrical cell-to-cell contact established with this interconnection technology. We combine this technology with a variable-geometry module design into an innovative digital inkjet printing platform for the production of state-of-the art but visually attractive solar modules. The full potential of this concept is demonstrated by a fully inkjet printed arbitrarily shaped OPV-M portrait