A5006040331- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Silicon and Solar Cell Technologies
- Perovskite Materials and Applications
- Thin-Film Transistor Technologies
- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Semiconductor materials and interfaces
- Photovoltaic System Optimization Techniques
- solar cell performance optimization
- Advanced Photocatalysis Techniques
- Silicon Nanostructures and Photoluminescence
- nanoparticles nucleation surface interactions
- Phase Equilibria and Thermodynamics
- Organic Light-Emitting Diodes Research
- Material Dynamics and Properties
- Photovoltaic Systems and Sustainability
- ZnO doping and properties
- Diverse Industrial Engineering Technologies
- Anodic Oxide Films and Nanostructures
- Solid-state spectroscopy and crystallography
- TiO2 Photocatalysis and Solar Cells
- Advanced Surface Polishing Techniques
- Semiconductor Quantum Structures and Devices
- Phase-change materials and chalcogenides
University of Potsdam
2020-2025
Paul Drude Institute for Solid State Electronics
2024-2025
Forschungsverbund Berlin
2024
Czech Academy of Sciences, Institute of Physics
2020-2024
Satbayev University
2017-2022
Institute of Physics and Technology
2014-2022
Institute of Astronomy
2020
Imperial College London
2007-2015
Al-Farabi Kazakh National University
2007-2013
A hybrid inorganic–polymer light-emitting diode that uses ZrO2 and MoO3 charge-injection layers exhibits enhanced electron injection allows the use of a variety red-, green-, blue-light-emitting polymers.
Simulated energy band diagrams of thin and thick PM6:Y6 devices.
Organic solar cells have many merits, including low cost and the ability to cover large flexible substrates, yet there is much room improve them. To maximize their efficiency, this study investigates effects of surface recombination in a model system, which work function electrode contacts varied via oxygen-plasma treatment. The authors explain how changing properties contact has profound effect not only on device but also interpretation optoelectronic measurements these devices.
Increasing the active layer thickness without sacrificing power conversion efficiency (PCE) is one of great challenges faced by organic solar cells (OSCs) for commercialization. Recently, PM6:Y6 as an OSC based on a non‐fullerene acceptor (NFA) has excited community because its PCE reaching high 15.9%; however, increasing thickness, drops due to reduction fill factor (FF). This drop attributed change in mobility ratio with thickness. Furthermore, this work demonstrates that regulating...
Perovskite semiconductors differ from most inorganic and organic due to the presence of mobile ions in material. Although phenomenon is intensively investigated, important questions such as exact impact on steady‐state power conversion efficiency (PCE) stability remain. Herein, a simple method proposed estimate loss via “fast‐hysteresis” measurements by preventing perturbation out their equilibrium position at fast scan speeds (1000 V s −1 ). The “ion‐free” PCE between 1% 3% higher than PCE,...
Mobile ions in perovskite photovoltaic devices can hinder performance and cause degradation by impeding charge extraction screening the internal field. Accurately quantifying mobile ion densities remains a challenge is highly debated topic. We assess suitability of several experimental methodologies for determining using drift-diffusion simulations. found that linearly increasing voltage (CELIV) underestimates density, but bias-assisted (BACE) accurately reproduce ionic lower than electrode...
The built-in voltage (VBI) is a key parameter for solar cell operation, yet in perovskite cells the distribution, magnitude, and origin of VBI remains poorly understood. In this work, we systematically studied pin-type based on different hole transport layers (TLs). To end, determine surface photovoltage (SPV) partial complete device stacks layer-by-layer by measuring work function (WF) under dark light (equivalent AM1.5G) conditions with Kelvin probe (KP) photoemission spectroscopy (UPS)...
A light-emitting diode based upon a three-component hybrid inorganic/organic nanocomposite film, comprising mesoporous TiO2 polymer adsorbed to the metal-oxide surface, and hole-transporting interpenetrated into film pores (see figure), is described: it allows luminescence charge-carrier transport processes be tuned individually.
Abstract Organic solar cells (OSC) nowadays match their inorganic competitors in terms of current production but lag behind with regards to open‐circuit voltage loss and fill‐factor, state‐of‐the‐art OSCs rarely displaying fill‐factor 80% above. The transport‐limited cells, including organic photovoltaic devices, is affected by material device‐specific parameters, whose combination represented the established figures merit, such as θ α. Herein, it demonstrated that these merit are closely...
Perovskite solar cells represent one of the recent success stories in photovoltaics. The device efficiency has been steadily increasing over past years, but further work is needed to enhance performance, for example, through reduction defects prevent carrier recombination. SCAPS-1D simulations were performed assess limits and identify approaches decrease impact defects, selection an optimal hole-transport material a hole-collecting electrode. Particular attention was given evaluation...
Abstract Low‐offset organic solar cell systems have attracted great interest since nonfullerene acceptors came into the picture. While numerous studies focused on charge generation process in these low‐offset systems, only a few details of each loss channel and their impact overall device performance. Here, several are blended with same polymer donor to form series where significant variation performance is observed. Through detailed analyses pathways, it found that: i) donor:acceptor...
The advantages of IR spectroscopy include relatively fast analysis and sensitivity, which facilitate its wide application in the pharmaceutical, chemical polymer sectors. Thus, provides an excellent opportunity to monitor degradation concomitant evolution molecular structure within a perovskite layer. As is well-known, one main limitations preventing industrialization solar cells low resistance various factors. aim this work was study surface thin film CH3NH3PbI3-xClx caused by atmosphere...
Abstract An organic bulk heterojunction based on a blend of conjugated polymer PBDB‐T‐2F (PM6) and non‐fullerene acceptor BTP‐4F (Y6) has come forward in recent years as an archetypical system for the study operating principles photovoltaic devices. One experimental techniques that shown immense value this is impedance spectroscopy (IS). In spite its relative simplicity, method derivatives offer possibility diverse, all‐round characterization materials devices interest. This Perspective...
The increase in the performance of organic solar cells observed over past few years has reinvigorated search for a deeper understanding loss and extraction processes this class device. A detailed knowledge density free charge carriers under different operating conditions illumination intensities is prerequisite to quantify recombination dynamics. Differential charging techniques are promising approach experimentally obtain carrier aforementioned conditions. In particular, combination...
The energetic offset between the highest occupied molecular orbitals of donor and acceptor components organic photovoltaic blends is well-known to affect device efficiency. It well-established that a decreasing increases open-circuit voltage but reduces short-circuit current, which has been explained by insufficient exciton dissociation. However, impact on fill factor underlying processes less clear. Here, we study free charge generation recombination in three different nonfullerene...
In this era of non-fullerene acceptor (NFA) based organic solar cells, reducing voltage losses while maintaining high photocurrents is the holy grail current research. Recent focus lies in understanding manifold fundamental mechanisms blends with minimal energy offsets - particularly relationship between ionization offset ({\Delta}IE) and free charge generation. We quantitatively probe multiple NFA-based by mixing Y5 Y6 NFAs PM6 varying molecular weights, covering a 15% to 1% power...
Abstract The interplay between free charge carriers, transfer (CT) states and singlet excitons (S 1 ) determines the recombination pathway resulting open circuit voltage ( V OC of organic solar cells. By combining a well‐aggregated low bandgap polymer with different blend ratios fullerenes PCBM ICBA, energy CT state E is varied by 130 meV while leaving S () unaffected. It found that exciton dominates radiative properties when approaches , remains limited non‐radiative decay state. concluded...
The time‐delayed collection field (TDCF) technique is a popular method to quantify the and temperature dependences of free charge generation in organic solar cells. Because relies on extraction photogenerated carriers, bimolecular recombination not only between carriers but also dark‐injected affects its accuracy, particularly at forward bias. In this work, drift–diffusion simulations are employed losses conventional modified TDCF measurements, where latter intends reduce impact dark...
Organic solar cell efficiency, exceeding 20%, is limited by recombination losses from singlet and triplet charge-transfer (CT) states local excitons, impacting open-circuit voltage (V OC ). Using PM6:o-IDTBR, a very low nonradiative loss, ΔV nr = 160 mV, achieved, despite the presence of excitons (6 × 1015 cm-3). In employing present system as model exemplar, we elucidate circumstance wherein, if lifetime surpasses CT decay, dissociation to state emerges feasible process. This, in turn,...
Structured absorbers: Mesoporous films of highly crystalline Sb2S3 are prepared from a doctor-bladed precursor paste that is thermally annealed. This facile and versatile processing route allows for control the pore size through variation annealing temperature. The resulting high surface area efficient charge transfer to polymeric hole acceptor; hence, such could form basis novel hybrid organic–inorganic photovoltaic device.
This paper considers the use of zinc oxide thin films prepared via sol-gel route as an n-type layer in heterojunction ZnO/Si solar cells. The ZnO were a simple spin-coating technique using acetate dihydrate precursor, isopropanol solvent and monoethanolamine stabilizing agent. Optical, structural morphological properties investigated for grown from solutions with different concentrations both on glass silicon substrates. As such, distribution crystallite sizes surface topology parameters...
Impedance spectroscopy provides relevant knowledge on the recombination and extraction of photogenerated charge carriers in various types photovoltaic devices. In particular, this method is great benefit to study crystalline silicon (c-Si)-based solar cells, a market-dominating commercial technology, for example, terms comparison c-Si This investigates dark light electrophysical characteristics heterojunction cell fabricated using plasma-enhanced chemical vapor deposition. The measurements...
Reducing voltage losses while maintaining high photocurrents is the holy grail of current research on non-fullerene acceptor (NFA) based organic solar cell. Recent focus lies in understanding various fundamental mechanisms blends with minimal energy offsets - particularly relationship between ionization offset (ΔIE) and free charge generation. Here, we quantitatively probe this multiple NFA-based by mixing Y-series NFAs PM6 different molecular weights, covering a broad power conversion...
Simultaneous thermal desorption and IR spectrometric studies of thermally stimulated transformations in thin films cryovacuum condensates water are carried out. It is shown that the temperature interval 12–36K existence region a high-density form amorphous solid water. The transition ice to low-density state starts at T≈39K completed 60–70K. This process accompanied by pore formation reaches its maximum intensity T≈42K. from glassy super-viscous liquid determined: Tg=137±2K. Further increase...
There is still no general consensus about the mechanism and nature of structural transformations in cryovacuum water ices. are different interpretations behavior cryoprecipitates with respect to proposed glass transition sequence values temperature Tg. The results an experimental investigation thermally stimulated polyamorphous polymorphous condensed films ices, formed at substrate 16K, presented. investigations performed frequency interval 4200–400cm−1 using a modified IR spectrophotometer....