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羟氨苄青霉素引起大疱性类天疱疮样疹

The photovoltaics of organic–inorganic lead halide perovskite materials have shown rapid improvements in solar cell performance, surpassing the top efficiency of semiconductor compounds such as CdTe and CIGS (copper indium gallium selenide) used in solar cells in just about a decade. Perovskite preparation via simple and inexpensive solution processes demonstrates the immense potential of this thin-film solar cell technology to become a low-cost alternative to the presently commercially available photovoltaic technologies. Significant developments in almost all aspects of perovskite solar cells and discoveries of some fascinating properties of such hybrid perovskites have been made recently. This Review describes the fundamentals, recent research progress, present status, and our views on future prospects of perovskite-based photovoltaics, with discussions focused on strategies to improve both intrinsic and extrinsic (environmental) stabilities of high-efficiency devices. Strategies and challenges regardi...

Halide Perovskite Photovoltaics: Background, Status, and Future Prospects

Gallium oxide (Ga2O3) is emerging as a viable candidate for certain classes of power electronics, solar blind UV photodetectors, solar cells, and sensors with capabilities beyond existing technologies due to its large bandgap. It is usually reported that there are five different polymorphs of Ga2O3, namely, the monoclinic (β-Ga2O3), rhombohedral (α), defective spinel (γ), cubic (δ), or orthorhombic (e) structures. Of these, the β-polymorph is the stable form under normal conditions and has been the most widely studied and utilized. Since melt growth techniques can be used to grow bulk crystals of β-GaO3, the cost of producing larger area, uniform substrates is potentially lower compared to the vapor growth techniques used to manufacture bulk crystals of GaN and SiC. The performance of technologically important high voltage rectifiers and enhancement-mode Metal-Oxide Field Effect Transistors benefit from the larger critical electric field of β-Ga2O3 relative to either SiC or GaN. However, the absence of clear demonstrations of p-type doping in Ga2O3, which may be a fundamental issue resulting from the band structure, makes it very difficult to simultaneously achieve low turn-on voltages and ultra-high breakdown. The purpose of this review is to summarize recent advances in the growth, processing, and device performance of the most widely studied polymorph, β-Ga2O3. The role of defects and impurities on the transport and optical properties of bulk, epitaxial, and nanostructures material, the difficulty in p-type doping, and the development of processing techniques like etching, contact formation, dielectrics for gate formation, and passivation are discussed. Areas where continued development is needed to fully exploit the properties of Ga2O3 are identified.

A review of Ga2O3 materials, processing, and devices

A Review of Perovskites Solar Cell Stability

In this work, a simple and efficient method for the extraction of all the parameters of a solar cell from a single current-voltage (I-V) curve under the constant illumination level is proposed. With the help of the Lambert W function, the explicit analytic expression for I is obtained. By reducing the number of the parameters, the expression for I only depends on the ideality factor n, the series resistance Rs, and the shunt resistance Rsh. This analytic expression is directly used to fit the experimental data and extract the device parameters. This simple solar cell parameter extraction method can be directly applied for all kinds of solar cells whose I-V characteristics follow the single-diode model. The parameters of various solar devices including silicon solar cells, silicon solar modules, dye-sensitized solar cells, and organic solar cells with standalone, tandem, and multi-junction structures have been successfully extracted by using our proposed method.

/pdf/a-simple-and-efficient-solar-cell-parameter-extraction-3p55aej9my.pdf

A simple and efficient solar cell parameter extraction method from a single current-voltage curve

Intermolecular Exchange Boosts Efficiency of Air-Stable, Carbon-Based All-Inorganic Planar CsPbIBr2 Perovskite Solar Cells to Over 9%

Recent research shows that the interface state in perovskite solar cells is the main factor which affects the stability and performance of the device, and interface engineering including strain engineering is an effective method to solve this issue. In this work, a CsBr buffer layer is inserted between NiO x hole transport layer and perovskite layer to relieve the lattice mismatch induced interface stress and induce more ordered crystal growth. The experimental and theoretical results show that the addition of the CsBr buffer layer optimizes the interface between the perovskite absorber layer and the NiO x hole transport layer, reduces interface defects and traps, and enhances the hole extraction/transfer. The experimental results show that the power conversion efficiency of optimal device reaches up to 19.7% which is significantly higher than the efficiency of the device without the CsBr buffer layer. Meanwhile, the device stability is also improved. This work provides a deep understanding of the NiO x /perovskite interface and provides a new strategy for interface optimization.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/advs.201903044

NiO/Perovskite Heterojunction Contact Engineering for Highly Efficient and Stable Perovskite Solar Cells

We report the first ferroelectric (FE) HfZrO x (HZO) Ge and GeSn pMOSFETs with sub-60 mV/decade subthreshold swing (SS) (40∼43 mV/decade), negligible hysteresis, and enhanced Ids. With a RTA at 450 oC, FE devices with reduced hysteresis of 40∼60 mV demonstrate the significantly improved SS and I ds characteristics compared to control devices without FE, owing to the negative capacitance (NC) effect induced by HZO. FE Ge and GeSn pFETs achieve 22% and 20% I ds enhancement than control devices, respectively, at the drive voltage of 1.0 V. NC effect in FE devices is proved by the gate leakage and inversion capacitance characteristics.

Ferroelectric HfZrO x Ge and GeSn PMOSFETs with Sub-60 mV/decade subthreshold swing, negligible hysteresis, and improved I ds

We have developed a novel AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistor using a stack gate HfO2/Al2O3 structure grown by atomic layer deposition. The stack gate consists of a thin HfO2 (30-A) gate dielectric and a thin Al2O3 (20- A) interfacial passivation layer (IPL). For the 50-A stack gate, no measurable C-V hysteresis and a smaller threshold voltage shift were observed, indicating that a high-quality interface can be achieved using a Al2O3 IPL on an AlGaN substrate. Good surface passivation effects of the Al2O3 IPL have also been confirmed by pulsed gate measurements. Devices with 1- mum gate lengths exhibit a cutoff frequency (fT) of 12 GHz and a maximum frequency of oscillation (f MAX) of 34 GHz, as well as a maximum drain current of 800 mA/mm and a peak transconductance of 150 mS/mm, whereas the gate leakage current is at least six orders of magnitude lower than that of the reference high-electron mobility transistors at a positive gate bias.

Jincheng Zhang

Papers

A simple and efficient solar cell parameter extraction method from a single current-voltage curve

Intermolecular Exchange Boosts Efficiency of Air-Stable, Carbon-Based All-Inorganic Planar CsPbIBr2 Perovskite Solar Cells to Over 9%

NiO/Perovskite Heterojunction Contact Engineering for Highly Efficient and Stable Perovskite Solar Cells

Ferroelectric HfZrO x Ge and GeSn PMOSFETs with Sub-60 mV/decade subthreshold swing, negligible hysteresis, and improved I ds

AlGaN/GaN MOS-HEMT With $\hbox{HfO}_{2}$ Dielectric and $\hbox{Al}_{2}\hbox{O}_{3}$ Interfacial Passivation Layer Grown by Atomic Layer Deposition