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In this study, the cytotoxicities and anti-inflammatory activities of five resveratrol derivatives—vitisinol A, (+)-ε-viniferin, (+)-vitisin A, (−)-vitisin B, and (+)-hopeaphenol—isolated from Ampelopsis brevipedunculata var. hancei were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lipopolysaccharide (LPS)-stimulated RAW264.7 cells, respectively. The result from MTT assay analysis indicated that vitisinol A has lower cytotoxicity than the other four well-known oligostilbenes. In the presence of vitisinol A (5 μM), the significant reduction of inflammation product (nitric oxide, NO) in LPS-induced RAW264.7 cells was measured using Griess reaction assay. In addition, the under-expressed inflammation factors cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in LPS-induced RAW264.7 cells monitored by Western blotting simultaneously suggested that vitisinol A has higher anti-inflammatory effect compared with other resveratrol derivatives. Finally, the anti-inflammatory effect of vitisinol A was further demonstrated on 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear edema in mice. As a preliminary functional evaluation of natural product, the anti-inflammatory effect of vitisinol A is the first to be examined and reported by this study.

Although much progress is made toward enhancing the efficiency of perovskite solar cells (PSCs), their operational reliability, particularly their mechanical stability, which is a crucial factor for flexible PSCs (f‐PCSs), has not attracted sufficient attention. The defects in the perovskite layer, especially on the top and the buried surface of the perovskite layer, can induce perovskite fracture, highly limiting the performance of f‐PSCs. Herein, a novel multifunctional organic salt, metformin hydrochloride, which can passivate cationic and anionic defects, is incorporated on both the top and buried surfaces of perovskite layer to suppress defects. As a result, a power conversion efficiency (PCE) of 24.40% for rigid PSCs and a PCE of 22.04% for f‐PSCs are achieved. Simultaneously, the device can retain 90% and 80% of the initial efficiency after 1000 h of light illumination and 10 000 bending cycles, respectively, showing excellent operational stability. This study may provide a global way to design a passivation strategy and fabricate flexible perovskite solar cells with high efficiency and stability.

Despite the low cost, safety and high theoretical capacity of metallic zinc, zinc anodes face chronic problems, including zinc dendrites, corrosion and side reactions in aqueous zinc-ion batteries (ZIBs). Herein, a nitrogen-doped carbon nanoparticle coating layer derived from discarded cigarette filters is constructed to suppress parasitic side reactions and zinc dendrite growth. The dense coating layer isolates water from the zinc anode, effectively inhibiting side reactions. Furthermore, the special micro-mesoporous structure and sufficient zincophilic groups guarantee uniform Zn stripping/plating. Consequently, durable cycle stability (2400 cycles at a current density of 1 mA cm-2) with a stable polarization potential is achieved for symmetrical cells. The coating layer derived in this study therefore has the potential to improve the electrochemical performance of ZIBs.

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