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It is well known that the different proportions of CuO and Cu2O in CuOx hole transfer materials have a great influence on the hole transport property as well as the device performances of perovskite solar cells (PSCs). In this paper, we changed the content of Cu2O in the film by controlling the deposition voltage during electrodeposition, and the effects of different contents of Cu2O in the films on the device were investigated for the first time. It was found that the content of Cu2O in the film reached the highest point with the deposition voltage 0.5 V, such films have the highest transmittance and carrier mobility. After assembling the device, the power conversion efficiency (PCE) of the champion device reached 13.48% under a one-sun AM 1.5 G (100 mW/cm 2) illumination. Furthermore, the unpackaged device based on CuOx still retained over 75% PCE after being placed in the ambient condition (30–40% humidity, 20–30 ∘ C) for 500 h. The content of Cu+ in the deposited film was controlled by changing the electrodeposition voltage. The content of Cu+ in the film reached the highest at a deposition voltage of 0.5 V. At the same time, the properties such as transmittance, carrier mobility and electrical conductivity of the film were optimized, and the PCE of the device was the highest. [ABSTRACT FROM AUTHOR]

Recently, perovskite solar cells (PSCs) have attracted more attention. TiO2 as the most common electron transfer material in PSCs has been improved by a serious of methods. In this study, a simple method was used to improve the traditional compact TiO2 properties by doping with Sn4+. It demonstrated that the conductivity of the TiO2 film could be well improved and the band-gap shifted from 3.65 to 3.55 eV with the introduction of Sn ions. The Sn–O–Ti bond was observed in the Sn:TiO2 film according to the results of XPS. The mesostructured PSCs based on Sn:TiO2 exhibited negligible J-V hysteresis behavior, and the Jsc of the device increased distinctly. The power conversion efficiency (PCE) of the Sn:TiO2 device was improved from 14.86 to 17.11%, compared with the reference device. [ABSTRACT FROM AUTHOR]

SnO2 as an ideal electron transfer material for planar halide perovskite solar cells has recently attracted much attention. However, the planar structure device shows significant hysteresis behavior and low optical stability due to numerous trap states and high UV transmittance. Here, carbon nanodots (CNDs) obtained by hydrothermal synthesis were firstly introduced into SnO2 ETLs through a simple solution process. Ultraviolet photoelectron spectroscopy, electronic impedance spectroscopy and UV-vis spectroscopy were used to investigate whether the introduction of CNDs increases the electronic coupling as well as energy levers which contribute to efficient electron extraction. The results showed that the introduction of CNDs could reduce the trap-state density and increase the mobility in SnO2 films. Finally, the device based on the SnO2:CNDs ETLs reached a high power conversion efficiency (PCE) of over 20% and steady-state PCE of 19.83% with negligible hysteresis. The SnO2:CNDs device retained over 90% of the initial PCE after storage in dry conditions for 1200 h and exhibited better UV stability after exposure to UV illumination. These results verify the simple method for producing highly efficient and UV stable perovskite solar cells. [ABSTRACT FROM AUTHOR]

Subwavelength gratings play a fundamental and pivotal role in numerous science and applications for wave manipulation, exhibiting distinctive features such as filtering, phase manipulation, and anti‐reflection. However, conventional fabrication methods for ultrasmall periodic structures are constrained by the fundamental optical diffraction limit, making it challenging to produce subwavelength gratings for optics. Here, a novel technique is demonstrated to build a reconfigurable subwavelength photorefractive grating (SPG) in a thin‐film lithium niobate on the platform of an optical microcavity. Such SPGs are optically induced through the photorefractive effect and the subwavelength features originate from the spatial phase modulations of the pump's standing wave. The resulting SPGs lead to the mode splitting of two counter‐propagating modes inside the microcavity, exhibiting an Electromagnetically Induced Transparency (EIT)‐like transmission spectrum. Moreover, the unique subwavelength characteristic of SPGs enables first‐order quasi‐phase‐matching for backward second‐harmonic generation, a long‐standing problem in nonlinear optics. Also, free‐space‐to‐chip vertical nonlinear frequency conversion can be achieved in a similar manner. These results provide a flexible approach toward fabricating subwavelength gratings, which holds significant potential in various applications such as nonlinear frequency conversion, optical communication, sensing, and quantum technologies. [ABSTRACT FROM AUTHOR]

For the first time, flash pyrolysis was carried out to fabricate polymer derived silicon oxycarbide (SiOC) ceramics. With the application of a DC electric field at a furnace temperature of only 780 °C, the SiOC ceramics exhibit characteristics that usually have to be pyrolyzed at ∼1300 °C. Both electric field and current density accelerate the SiOC microstructure development, causing carbon and SiC phases to form at >520 °C lower pyrolysis temperatures than conventional within the SiOC matrix. With higher electric fields, the samples experience greater mass loss and linear shrinkage, while also forming more SiC and a more ordered carbon phase. The SiC formation inversely impacts the carbon content, causing a decrease in electrical conductivity. Further, reducing current density results in significant carbon precipitation without SiC formation. The fundamentals can be explained based on increased nucleation rate by the electrical field, accompanied by Joule heating and electromigration. This work is the first to demonstrate the great potential of flash pyrolysis on accelerated phase separation of polymer derived SiOC. [ABSTRACT FROM AUTHOR]

Silicon oxycarbide (SiOC) is an important polymer derived ceramic with many unique properties such as high temperature stability and amorphous-nanocrystalline mixed structures. It can be made using different processing routes. In this study, SiOC ceramics were investigated using a polysiloxane precursor crosslinked in the presence of 0, 100, 200, and 300 vol% of 3-pentanone as the solvent. The microstructure and the phase evolution during pyrolysis depend on the solvent concentration during crosslinking. The addition of pentanone facilitates the formation of nanocrystalline SiC at pyrolysis temperatures ≤1300 °C. However, the formation of SiC decreases with increasing solvent content when pyrolyzed at 1400 °C. Simply varying the solvent concentration during crosslinking provides a unique and tunable processing route for modifying the phase formation within SiOC ceramics. [ABSTRACT FROM AUTHOR]

[Display omitted] • SalA reduces the levels of atherosclerosis-related protein OPN and vascular inflammation marker CRP protein and ameliorates the aortic damage caused by renal injury. • SalA exerts a protective function against kidney injury-induced cardiovascular injury by resisting oxidative stress and through the PI3K/Akt/Nrf 2/HO-1 pathway. • SalA plays a protective role in renal injury-induced vascular injury by inhibiting the inflammatory response and through the SIRT 1/TLR 4/NF/κ B/P38 pathway. Salvianolic acid A (Sal A), extracted from Danshen, has proven efficacy in preventing cardiovascular diseases. However, its effect on mitigating vascular damage caused by chronic kidney disease remains unclear. This study investigated the therapeutic effects and underlying mechanisms of Sal A in a rat model of 5/6 Nephrectomized (5/6Nx). The results of our study showed that Sal A effectively reduced the levels of kidney injury markers. Histopathological analysis revealed that Sal A dose-dependently attenuated arterial injury. The attenuation was characterized by the thinning of vascular endothelium and reduced endothelial cell hyperplasia, accompanied by decreased expression of OPN and C-Reaction Protein (CRP). Further investigations revealed that Sal A alleviated oxidative stress-induced vascular injury by activating the Phosphoinositide 3-kinase (PI3K)/Protein Kinase B(Akt)/Nuclear factor erythroid2-related factor 2(Nrf2)/Heme Oxygenase 1(HO-1) signaling pathway. Furthermore, Sal A inhibited inflammation by suppressing the Sirtuin-1(SIRT1)/Toll-like receptor 4(TLR4)/Nuclear factor kappa-B(NF-κB)/P38 signaling pathway and reducing the expression of pro-inflammatory cytokines. Our oxidative stress and inflammation cell models also supported these findings. In conclusion, Sal A treatment effectively attenuated vascular injury in 5/6Nx rats and exerted dual antioxidant and anti-inflammatory effects. [ABSTRACT FROM AUTHOR]

A new kind of photovoltaic material, copper yttrium selenide (CuYSe 2 ) was synthesized using a self-propagating high-temperature synthesis method. Here the reaction process of the SHS process of CuYSe 2 has been illustrated. The crystalline structure and morphology of the CuYSe 2 powders were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The band gap of the CuYSe 2 material was estimated to be 1.53 eV based on the UV–vis spectrum of the material. Thin films of CuYSe 2 were prepared using a simple, low-cost non-vacuum method. The current-voltage (I-V) behavior of CuYSe 2 photovoltaic device was determined. The I light /I dark ratio of the CuYSe 2 device was found to be 2.81, implying that CuYSe 2 is a very promising candidate for application as the absorption materials in thin film solar cells. [ABSTRACT FROM AUTHOR]