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Subnanocluster (SNC) cocatalysts are considered to be promising cocatalysts for photocatalytic hydrogen evolution reaction (HER) due to their rich surface-active sites and high atom utilization efficiency. Herein, a reductant-mediated in situ growth of the atomic clusters procedure is developed to synthesize SNC-Cu serving as advanced cocatalysts on TiO2 nanoparticles for HER. The optimized SNC-Cu/TiO2 catalyst, with 1.8 wt % metal mass loading, exhibits a remarkable hydrogen evolution rate of 6832 μmol g–1 h–1, which is ca. 25-fold that of bare TiO2 (273 μmol g–1 h–1 and comparable to that of 1 wt % Pt-modified TiO2 (7754 μmol g–1 h–1). Meanwhile, decent photostability and recyclability are also certified via a 20 h durability test. Comprehensive electron microscopy and spectroscopy characterizations unveil that the outstanding performance of SNC-Cu/TiO2 can be attributed to accelerated charge separation/transfer and suppressed photoinduced electron–hole recombination. Furthermore, in situ X-ray photoelectron spectroscopy and first-principle calculations reveal that the electron-localized SNC-Cu, with its abundant surface sites, facilitates *H adsorption and desorption, thus enhancing the HER activity significantly. This work highlights the promising potential of constructing noble-metal-free SNCs in semiconductors for photocatalytic HER. [ABSTRACT FROM AUTHOR]

Herein, we introduce an electrochemical dehydrogenative [3 + 2]/[5 + 2] annulation of easily available N -arylacrylamides with γ,σ-unsaturated malonates through C(sp 3 )-H/C(sp 2 )-H functionalization. The employment of inexpensive ferrocene as the redox catalyst allows access to diverse benzo[ b ]azepin-2-ones in moderate to excellent yields without stoichiometric oxidants. This protocol features broad substrate scope and excellent selectivity, and mechanistic studies indicated that the reaction proceeded through the oxidation of a C(sp 3 )-H bond to generate an alkyl radical, radical addition across the C═C bond, [3 + 2]/[5 + 2] annulations, and C(sp 2 )-H functionalization cascades.

The wettable surface or nonwettable surface that is derived from a multilevel micronanoscale structure is abundant in nature and biomimetic commodities. Those hoverflies with the seta-coated wing membrane detached from impacting free-falling raindrops were observed in static states. A hoverfly wing membrane with well-ordered setae was identified as a robust nonwettable surface, and the static water contact angle θ on the wing membrane at the microscopic scale is 136.84 ± 0.98°. Hoverfly wing membrane-water droplet interaction with the actual truth and the theoretical models was discussed and indicated that the theoretical calculation might not state the actual situation, arising from the membrane or seta-drop-bubble interaction and those multilevel micronanoscale structure characteristics on the wing membrane. Detailed investigation on nonwettable surface-wettable surface transformation with surface CaCO 3 accumulation in a carbonization reaction and the characteristic transformation toward the hoverfly wing membrane with the multilevel micronanoscale structure was carried out. Then, the CaCO 3 accumulation on PDMS texture films was carried out and the static water contact angle θ was tested. Those observations offer ideas to fabricate artificial films with a multilevel micronanoscale structure that could obtain some characteristics, i.e., nonwettable surface-wettable surface transformation.