To improve the quantum efficiency and stability of perovskite quantum dots, the structural and optical properties are optimized by varying the concentration of Ni doping in CsPbBr3 perovskite nanocrystals (PNCs). As Ni doping is gradually added, a blue shift is observed at the photoluminescence (PL) spectra. Ni‐doped PNCs exhibit stronger light emission, higher quantum efficiency, and longer lifetimes than undoped PNCs. The doped divalent element acts as a defect in the perovskite structure, reducing the recombination rate of electrons and holes. A stability test is used to assess the susceptibility of the perovskite to light and moisture. For ultra‐violet light irradiation, the PL intensity of undoped PNCs decreases by 70%, whereas that of Ni‐doped PNCs decreases by 18%. In the water addition experiment, the PL intensity of Ni‐doped PNCs is three times that of undoped PNCs. For CsPbBr3 and Ni:CsPbBr3 PNCs, a light emitting diode is fabricated by spin‐coating. The efficiency of Ni:CsPbBr3 exceeds that of CsPbBr3 PNCs, and the results significantly differ based on the ratio. A maximum luminance of 833 cd m–2 is obtained at optimum efficiency (0.3 cd A–1). Therefore, Ni‐doped PNCs are expected to contribute to future performance improvements in display devices.

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P–N heterostructures based on transition-metal dichelcongenides (TMDs) and a conventional semiconductor, such as p-Si, have been considered a promising structure for next-generation electronic devices and applications. However, synthesis of high-quality, wafer-scale TMDs, particularly WS2 on p-Si, is challenging. Herein, we propose an efficient method to directly grow WS2 crystals on p-Si via a hybrid thermolysis process. The WO3 is deposited to prepare the p-Si surface for coating of the (NH4)2WS4 precursor and converted to WS2/p-Si during thermolysis. Moreover, the WS2/p-Si heterojunction photocathode is fabricated and used in solar hydrogen production. The fabricated n-WS2/p-Si heterojunction provided an onset potential of +0.022 V at 10 mA/cm2 and a benchmark current density of −9.8 ± 1.2 mA/cm2 at 0 V. This method reliably and efficiently produced high-quality, wafer-scale WS2 crystals and overcame the challenges associated with previous approaches. The approach developed in this research demonstrates a magnificent progress in the fabrication of 2D material-based electronic devices.

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A new terthiophene, 3'-hydroxy-2,2':5',2″-terthiophene-3'-O-β-D-glucopyranoside (1) and a new oleanane-type saponin, echinocystic acid-3-O-(6-O-acetyl)-β-D-glucopyranoside (7) were isolated from the aerial parts of Eclipta prostrata L. Moreover, five thiophenes (2-6), seven triterpenoids (8-14), two coumestans (15 and 16), and four flavonoids (17-20) having previously known chemical structures were isolated during the same course of this study. All the isolates 1-20 were evaluated for their cytotoxicity against human ovarian cancer cells (SKOV3) using MTT assays.

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Naringin is a flavanone glycoside in citrus fruits that has various biological functions. However, its bitterness affects the quality, economic value, and consumer acceptability of citrus products. Deglycosylation of naringin using naringinase decreases its bitterness and enhances its functional properties. In this study, eight microbial strains with naringinase activity were isolated from 33 yuzu-based fermented foods. Among them, naringinase from Aspergillus oryzae NYO-2, having the highest activity, was used to produce prunin and naringenin. Under optimal conditions, 19 mM naringin was converted to 14.06 mM prunin and 1.97 mM naringenin. The bitterness of prunin and naringenin was significantly decreased compared to naringin using the human bitter taste receptor TAS2R39. The neuroprotective effects of prunin and naringenin on human neuroblastoma SH-SY5Y cells treated with scopolamine were greater than that of naringin. These findings can widen the potential applications of deglycosylation of naringin to improve sensory and functional properties.