A5086295160- Conducting polymers and applications
- Organic Electronics and Photovoltaics
- Perovskite Materials and Applications
- 3D Printing in Biomedical Research
- Innovative Microfluidic and Catalytic Techniques Innovation
- Microfluidic and Bio-sensing Technologies
- Advanced MEMS and NEMS Technologies
- Chalcogenide Semiconductor Thin Films
- Electrowetting and Microfluidic Technologies
- Microfluidic and Capillary Electrophoresis Applications
- Cellular Mechanics and Interactions
- Quantum Dots Synthesis And Properties
- Thin-Film Transistor Technologies
- Bacterial biofilms and quorum sensing
- Organic Light-Emitting Diodes Research
- Advanced Sensor and Energy Harvesting Materials
- Tissue Engineering and Regenerative Medicine
- Solid-state spectroscopy and crystallography
- Sensor Technology and Measurement Systems
- Biosensors and Analytical Detection
- Vibrio bacteria research studies
- Mechatronics Education and Applications
- Nanofabrication and Lithography Techniques
- Electrical and Thermal Properties of Materials
- Advanced Surface Polishing Techniques
Technische Universität Braunschweig
2019-2025
HeidelbergCement (Germany)
2020
Heidelberg University
2017-2019
National University of Singapore
2019
Pontificia Universidad Católica de Chile
2019
Hong Kong University of Science and Technology
2019
University of Hong Kong
2019
Shenzhen Metro (China)
2019
DKFZ-ZMBH Alliance
2019
North Carolina State University
2015-2018
Through detailed device characterization using cross‐sectional Kelvin probe force microscopy (KPFM) and trap density of states measurements, we identify that the J – V hysteresis seen in planar organic–inorganic hybrid perovskite solar cells (PVSCs) SnO 2 electron selective layers (ESLs) synthesized by low‐temperature plasma‐enhanced atomic‐layer deposition (PEALD) method is mainly caused imbalanced charge transportation between ESL/perovskite hole layer/perovskite interfaces. We find this...
Abstract Low‐bandgap mixed tin–lead perovskite solar cells (PSCs) have been attracting increasing interest due to their appropriate bandgaps and promising application build efficient all‐perovskite tandem cells, an effective way break the Shockley–Queisser limit of single‐junction cells. Tin fluoride (SnF 2 ) has widely used as a basis along with various strategies improve optoelectronic properties low‐bandgap SnPb perovskites However, fully understanding roles SnF in both films devices is...
Epithelial cells respond to infection with the intracellular bacterial pathogen Listeria monocytogenes by altering their mechanics promote collective infected cell extrusion (CICE) and limit spread across monolayers. However, underlying biochemical pathways remain elusive. Here, using in vitro (epithelial monolayers) vivo (zebrafish larvae) models of L. or Shigella flexneri, we explored role extracellular-signal-regulated kinase (ERK) activity waves coordinating mechanical battle between...
A detailed investigation of the impact molecular weight distribution a photoactive polymer, poly[ N ‐9′‐heptadecanyl‐2,7‐carbazole‐ alt ‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), on photovoltaic device performance and carrier transport properties is reported. It found that different batches as‐received polymers have substantial differences in their distribution. As revealed by gel permeation chromatography (GPC), two peaks can generally be observed. One corresponds to...
Thin-film optoelectronic devices based on polycrystalline organolead-halide perovskites have recently become a topic of intense research. Single crystals these materials been grown from solution with electrical properties superior to those films. In order enable the development more complex device architectures perovskite single crystals, we developed process form epitaxial layers methylammonium lead iodide (MAPbI3) bromide (MAPbBr3) crystals. The formation MAPbI3 layer is found be dominated...
From deciphering infection and disease mechanisms to identifying novel biomarkers personalizing treatments, the characteristics of individual cells can provide significant insights into a variety biological processes facilitate decision‐making in biomedical environments. Conventional single‐cell analysis methods are limited terms cost, contamination risks, sample volumes, times, throughput, sensitivity, selectivity. Although microfluidic approaches have been suggested as low‐cost,...
Abstract Incorporating mechanical stretching of cells in tissue culture is crucial for mimicking (patho)‐physiological conditions and understanding the mechanobiological responses cells, which can have significant implications areas like engineering regenerative medicine. Despite growing interest, most available cell‐stretching devices are not compatible with automated live‐cell imaging, indispensable characterizing alterations dynamics various important cellular processes. In this work,...
Two-phase biocatalysis in batch reactions often suffers from inefficient mass transfer, inconsistent reaction conditions, and enzyme inactivation issues. Microfluidics offer uniform controlled environments ensuring better reproducibility enable efficient, parallel processing of many small-scale reactions, making more scalable. In particular, the use microfluidic droplets can increase interfacial area between two phases therefore also rates. For these reasons, slug flow has been extensively...
It is commonly believed that large dielectric constants are required for efficient charge separation in polymer photovoltaic devices. However, many polymers used high‐performance solar cells do not possess high constants. In this work, the effect of polymer–fullerene interactions on environment active layer blend and device performance several donor–acceptor conjugated systems investigated. found that, while none high‐performing studied has a constant value larger than 3, all blends have...
Abstract Despite the rapid development of nonfullerene acceptors (NFAs), fundamental understanding on relationship between NFA molecular architecture, morphology, and device performance is still lacking. Herein, poly[[4,8‐bis[5‐(2‐ethylhexyl)thiophene‐2‐yl]benzo[1,2‐b:4,5‐b0]dithiophene‐2,6‐diyl][3‐fluoro‐2‐[(2‐ethylhexyl)carbonyl]‐thieno[3,4‐b]thiophenediyl]] (PTB7‐Th) used as donor polymer to compare an with a 3D architecture (SF‐PDI4) well‐studied linear acceptor–donor–acceptor (A–D–A)...
The morphological evolution is initiated by L–L or L–S phase separation (left) and further developed molecular mobility, governed polymer–solvent interactions which determine the final domain size of BHJ layer (right).
Non-fullerene acceptors (NFAs) are becoming a serious contender to fullerene-based electron in organic photovoltaics, due their structural versatility and easily tunable optical electronic properties.
As many conjugated polymer-based organic photovoltaic (OPV) materials provide substantial solar power conversion efficiencies (as high as 13%), it is important to develop a deeper understanding of how the primary repeat unit structures impact device performance. In this work, we have varied group 14 atom (C, Si, Ge) at center bithiophene fused ring elucidate minimal structure change on optical, transport, and morphological properties, which ultimately control Careful polymerization polymer...
Abstract Power conversion efficiency (PCE) of lead (Pb)‐free tin (Sn)‐based perovskite solar cells (PVSCs) is much lower than that their Pb‐based counterparts, which mainly attributed to large open‐circuit voltage ( V OC ) loss and poor fill factor (FF). In this work, a strategy via vacuum‐assisted treatment the Sn layer self‐heal defects in reported, leading suppression nonradiative recombination enhancement carrier transport capability. Using method, maximum PCE 10.3% obtained for dual...
Abstract Although ternary solar cells (TSCs) offer a cost‐effective prospect to expand the absorption bandwidth of organic cells, only few TSCs have succeeded in surpassing performance binary (BSCs) primarily due complicated morphology blends. Here, key factors that create and limit are elucidated. The origin formation is explored role kinetic investigated. results reveal TSC blends considered this study characterized with either single length‐scale or two features depending on composition...
The effects of the oligothiophene length two thiophene-isoindigo copolymers on film morphology, charge transfer, and photovoltaic device performance are reported. Despite similarities in their repeat unit structures, polymers show distinctly different morphologies upon blending with PC71BM. We found that there is a significant increase dielectric constant photoactive fullerene polymer exhibits higher power conversion efficiency. Blend photoluminescence transients revealed fast dissociation...
The effect of air processing, with exposure varying from minutes to hours prior encapsulation, on photovoltaic device performance has been studied through a series electrical characterizations and optical simulations for donor/acceptor polymer-based organic solar cell based poly(dithienogermole-alt-thienopyrrolodione) p(DTG-TPD)/PC71BM blends. A ∼10% degradation in power conversion efficiency was observed due processing 10 min time, AM1.5 efficiencies (PCEs) decreasing 8.5 ± 0.25% devices...
Abstract Wide-bandgap (wide- E g , ∼1.7 eV or higher) perovskite solar cells (PSCs) have attracted extensive attention due to the great potential of fabricating high-performance perovskite-based tandem via combining with low-bandgap absorbers, which is considered promising exceed Shockley–Queisser efficiency limit. However, inverted wide- PSCs a minimized open-circuit voltage ( V oc ) loss, are more suitable prepare all-perovskite devices, still lacking study. Here, we report strategy adding...
The role of excess excitation energy on long‐range charge separation in organic donor/acceptor bulk heterojunctions (BHJs) continues to be unclear. While ultrafast spectroscopy results argue for efficient through high‐energy charge‐transfer (CT) states within the first picosecond (ps) excitation, collection measurements suggest photon does not increase current density BHJ devices. Here, population dynamics charge‐separated polarons upon polymer and low‐energy interfacial CT two...
The effect of polymer side chains on device performance was investigated for PBDT(EtHex)-TPD(Oct):PC70BM and PBDT(EtHex)-TPD(EtHex):PC70BM BHJ solar cells. Going from a linear chain the polymer's acceptor moiety to branched determined have negative impact overall efficiency, because significantly reduced short-circuit current (J(sc)) fill factor (FF) values. Sub-bandgap external quantum efficiency (EQE) transient photoluminescence (PL) measurements showed more-efficient carrier generation...