Bi-self-doped BiVO (Bi-BVO) nanotubes with p-n homojunctions are fabricated via an oxygen-induced strategy. Calcinating the as-spun fibers with abundant oxygen plays a pivotal role in achieving Bi self-doping. Density functional theory calculations and experimental results indicate that Bi self-doping can narrow the band gap of BiVO, which contributes to enhancing light harvesting. Moreover, Bi self-doping endows BiVO with n- and p-type semiconductor characteristics simultaneously, resulting in the construction of p-n homojunctions for retarding rapid electron-hole recombination. Benefiting from these favorable properties, Bi-BVO exhibits a superior photocatalytic performance in contrast to that of pristine BiVO. Furthermore, this is the first report describing the achievement of p-n homojunctions through self-doping, which gives full play to the advantages of self-doping.

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Objective (s) Accumulating evidence has suggested that oxidative stress and apoptosis are involved in the aging process. d ‐galactose (gal) has been reported to cause symptoms of aging in mice, accompanied by liver and brain injuries. Our present work was to study the potential antioxidative and anti‐apoptotic effects of walnut and to explore how these effects act on mice in a d ‐gal‐induced aging model. Materials and Methods Aging mice were induced by subcutaneous injection of d ‐gal (200 mg kg −1 d −1 for 8 weeks). Walnut samples were simultaneously administered to the d ‐gal‐induced aging mice once daily by intragastric gavage. Finally, body weight, organ index, cognitive function, levels of antioxidative enzymes, and liver function were monitored. Results The kernel pellicles of walnut could not only improve the learning and memory ability, and the organ index, but also significantly decrease body weight and normalize the levels of activity of antioxidative enzymes in aging mice. Further, the walnut seed coat would protect damages of hippocampus and liver in aging mice. Highlights In the current study, we investigated the effects of walnut kernels and walnut seed coats (WSCs) on d ‐galactose‐induced aging mice. WSC was firstly found to have beneficial effects on d ‐gal‐treated mouse's brain with learning and memory impairment, which probably through the underlying mechanism reduces oxidative damage and limits neuroinflammation. In addition, WSC had a protective effect on liver damage in d ‐galactose sensing mice.

Upconverting infrared light into visible light via the triplet-triplet annihilation process in solid state is important for various applications including photovoltaics, photodetection, and bioimaging. Although inorganic semiconductors with broad absorption and negligible exchange energy loss have emerged as promising alternative to molecular sensitizers, currently, they have exclusively suffered from low efficiency and contained toxic elements in near-infrared (NIR)–to–visible upconversion. Here, we report an ultrathin bilayer film for NIR-to-visible upconversion based on atomically thin two-dimensional (2D) monolayer semiconductors. The atomic flatness and strong light absorption of 2D monolayer semiconductors enable ultrafast energy transfer and robust NIR-to-visible emission with a high upconversion quantum yield (1.1 ± 0.2%) at modest incident power (260 mW cm −2 ). Increasing layer thickness adversely quenches the upconversion emission, highlighting the 2D advantage. Considering the whole library of 2D semiconductors, the facile large-scale production and the ultrathin solid-state architecture open a new research field for solid-state upconversion applications.

Heterostructures built from two-dimensional (2D) materials and organic semiconductors offer a unique platform for addressing many fundamental physics and construction of functional devices by taking both the advantages of 2D...