Evgeniia Gilshtein

Bio: Evgeniia Gilshtein is an academic researcher from Swiss Federal Laboratories for Materials Science and Technology. The author has contributed to research in topics: Materials science & Perovskite (structure). The author has an hindex of 6, co-authored 15 publications receiving 60 citations. Previous affiliations of Evgeniia Gilshtein include Skolkovo Institute of Science and Technology.

ZnO Nanostructures Application in Electrochemistry: Influence of Morphology

Abstract: The aim of this work was to investigate the influence of morphology on its electrochemical properties by comparing ZnO nanostructures in the forms of tetrapods of different sizes, nanorods, and nan...

Revealing the perovskite formation kinetics during chemical vapour deposition

Abstract: Amongst a number of deposition methods for perovskite layers, vapour based ones are promising for large area industrial production of solar cells. Different variants of such methods and high efficiencies have been reported recently, but there remains a lack of understanding on the formation process of perovskite layers with 2-step vapour deposition. Here, we present a new reactor design for a controlled investigation of the reaction kinetics for conversion of an evaporated metal halide precursor layer (such as a mixture of lead iodide and cesium bromide) into a perovskite layer by exposure to an organo-halide (such as formamidinium iodide) vapour under stable isobaric–isothermal conditions. With this new concept of gas flow reversal in a tubular reactor, we overcome an inherent problem of the lack of control over the precise start and end of the conversion process. We investigated the formation reaction of a mixed cation (Cs0.04FA0.96)PbI3 perovskite in well-defined intermediate states to elucidate the influence of processing conditions on the kinetics of perovskite and other phase formations. A high conversion rate of up to 60 nm min−1 is achieved with a well-controlled abrupt start and end of the vapor supply. Using our deposition method, a semitransparent solar cell with a power conversion efficiency (maximum power tracking) of 9.6% on a designated area of 0.27 cm2 is achieved in the initial phase of development where the charge extracting layers and interfaces are yet to be optimised.

Synaptic transistors with aluminum oxide dielectrics enabling full audio frequency range signal processing.

Abstract: The rapid evolution of the neuromorphic computing stimulates the search for novel brain-inspired electronic devices. Synaptic transistors are three-terminal devices that can mimic the chemical synapses while consuming low power, whereby an insulating dielectric layer physically separates output and input signals from each other. Appropriate choice of the dielectric is crucial in achieving a wide range of operation frequencies in these devices. Here we report synaptic transistors with printed aluminum oxide dielectrics, improving the operation frequency of solution-processed synaptic transistors by almost two orders of magnitude to 50 kHz. Fabricated devices, yielding synaptic response for all audio frequencies (20 Hz to 20 kHz), are employed in an acoustic response system to show the potential for future research in neuro-acoustic signal processing with printed oxide electronics.

Electrochemical Impedance Spectroscopy (EIS): Principles, Construction, and Biosensing Applications

Abstract: Electrochemical impedance spectroscopy (EIS) is a powerful technique used for the analysis of interfacial properties related to bio-recognition events occurring at the electrode surface, such as antibody-antigen recognition, substrate-enzyme interaction, or whole cell capturing. Thus, EIS could be exploited in several important biomedical diagnosis and environmental applications. However, the EIS is one of the most complex electrochemical methods, therefore, this review introduced the basic concepts and the theoretical background of the impedimetric technique along with the state of the art of the impedimetric biosensors and the impact of nanomaterials on the EIS performance. The use of nanomaterials such as nanoparticles, nanotubes, nanowires, and nanocomposites provided catalytic activity, enhanced sensing elements immobilization, promoted faster electron transfer, and increased reliability and accuracy of the reported EIS sensors. Thus, the EIS was used for the effective quantitative and qualitative detections of pathogens, DNA, cancer-associated biomarkers, etc. Through this review article, intensive literature review is provided to highlight the impact of nanomaterials on enhancing the analytical features of impedimetric biosensors.

Intrinsic DX Centers in Ternary Chalcopyrite Semiconductors

Abstract: The conclusions of this report are: (1) intrinsic donor-type defects In{sub Cu}, Ga{sub Cu}, and V{sub Se}, and their complexes with V{sub Cu} cause metastability, but also act to limit V{sub OC}; (2) growth conditions which minimize these defects (Cu-rich/Se-rich) are very different from those currently used; and (3) overcoming V{sub OC} limitation requires to address other issues and trade-offs.

Wide Bandgap Oxide Semiconductors: from Materials Physics to Optoelectronic Devices

Abstract: Wide bandgap oxide semiconductors constitute a unique class of materials that combine properties of electrical conductivity and optical transparency. They are being widely used as key materials in optoelectronic device applications, including flat-panel displays, solar cells, OLED, and emerging flexible and transparent electronics. In this article, an up-to-date review on both the fundamental understanding of materials physics of oxide semiconductors, and recent research progress on design of new materials and high-performing thin film transistor (TFT) devices in the context of fundamental understanding is presented. In particular, an in depth overview is first provided on current understanding of the electronic structures, defect and doping chemistry, optical and transport properties of oxide semiconductors, which provide essential guiding principles for new material design and device optimization. With these principles, recent advances in design of p-type oxide semiconductors, new approaches for achieving cost-effective transparent (flexible) electrodes, and the creation of high mobility 2D electron gas (2DEG) at oxide surfaces and interfaces with a wealth of fascinating physical properties of great potential for novel device design are then reviewed. Finally, recent progress and perspective of oxide TFT based on new oxide semiconductors, 2DEG, and low-temperature solution processed oxide semiconductor for flexible electronics will be reviewed.

Inkjet printing for flexible and wearable electronics

Abstract: Flexible and wearable electronic devices are emerging as the novel platform for portable health monitoring, human–machine interaction, and some other electronic/optic applications. Future development of human-friendly smart electronics relies on efficient manufacturing and processing of advanced functional materials on flexible/stretchable substrates with effective device integration. Inkjet printing, known as a highly efficient solution-based printing and patterning technology with low-cost, high-quality, and high-throughput advantages, suits large-scale fabrication of flexible and wearable electronics. Over the years, researchers focused on high pattern resolution and uniformity on flexible substrates for advanced electrical/optical performances by various inkjet printing techniques. Different ink materials that can realize multiple functions have been fully investigated for achieving favorable printability and desired interactions with the substrates. Here, the most recently reported inkjet printing strategies, functional ink materials, and diverse inkjet-printed wearable electronic devices for practical applications (e.g., sensors, displays, transistors, and energy storage devices) are summarized. An outlook on future challenges as well as opportunities of inkjet-printed flexible and wearable electronics for research development and industrial commercialization is also presented.