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Herein, we present the divergent syntheses of α‐arylacylamides and oxindoles via mechanoredox chemistry by using easily accessible α‐bromo N‐sulfonyl amides as starting materials. Our system consists of a catalytic amount of CuII precatalyst and piezoelectric materials. The highly polarized BaTiO3 or PbTiO3 under mechanical agitation can act as an electron donor to realize the recycling of CuII and CuI. Control experiments and density functional theory calculations have been performed to support the proposed mechanistic rationale for the cascade reactions. [ABSTRACT FROM AUTHOR]

Achieving efficient photocatalytic degradation of atmospheric volatile organic compounds (VOCs) under sun-light is still a significant challenge for environmental protection. The S-scheme heterojunction with its unique charge migration route, high charge separation rate and strong redox ability, has great potential. However, how to regulate interfacial charge transfer of the S-scheme heterojunction is of significant importance. Here, density functional theory (DFT) calculations were first conducted and predicted that an S-scheme heterojunction could be formed in the CdS quantum dots/Bi 2 MoO 6 monolayer system. Subsequently, this novel heterojunction is constructed by in-situ hydrothermal synthesis of CdS quantum dots on monolayer Bi 2 MoO 6. Under visible-light, this novel S-scheme system gives a high-efficiency photocatalytic degradation rate (6.04 × 10−2 min−1) towards C 2 H 4 , which is 30.3 times higher than that of pure CdS (1.99 × 10−3 min−1) and 41.7 times higher than pure Bi 2 MoO 6 (1.45 × 10−3 min−1). Strong evidence for the S-scheme charge transfer path is provided by in-situ XPS, PL, TRPL and EPR. [Display omitted] • A novel S-scheme CdS QDs/Bi 2 MoO 6 monolayer photocatalyst was synthesized. • This S-scheme heterojunction shows excellent activities for C 2 H 4 photodegradation. • The reaction mechanism of C 2 H 4 photooxidation was comprehensively investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Designed and fabricated a CdS QDs/Bi 2 WO 6 monolayer S-scheme heterojunction. • Bi-S bonds deliberately introduced at the interface to regulate the charge transfer. • S-scheme heterojunction show excellent photoactivities for C 2 H 4 oxidation. The S-scheme heterojunction with unique photogenerated electrons and holes migration pathway, excellent separation efficiency of photogenerated carrier and high redox potential, has great potential in this field of photocatalytic oxidation of atmospheric C 2 H 4. However, optimising the transfer of photogenerated charge at the S-scheme heterostructure interface continues to a major challenge. Here, density functional theory (DFT) calculations were first conducted to predict an S-scheme heterojunction can be formed in the CdS quantum dots (QDs)/Bi 2 WO 6 monolayer system, and then CdS QDs/Bi 2 WO 6 monolayer S-scheme heterojunction were constructed by in-situ hydrothermal synthesis of CdS QDs onto Bi 2 WO 6 monolayer. Bi-S bonds are deliberately introduced at the interface to maximise the photogenerated charge transfer. As expected, the substantial enhancement of the photocatalytic degradation of ethylene and the photostabilization of CdS is demonstrated. The S-scheme band alignment and the connected Bi-S coordination introduced at the junction interface allow highly efficient charge separation and an effective interfacial charge migration path. This research provides a basis for understanding the design of materials for the removal of hydrocarbons in air and environmental pollutant remediation, and improving the stability of sulfide and other photocatalysts to photocorrosion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Doped transition metals provide more active reaction center for NRR. • Fe@Tr-COF and Ni@Tr-COF exhibit higher N 2 absorption in the visible and IR regions. • The NRR for Fe@Tr-COF and Ni@Tr-cof involves energy utilizations. • TM@Tr-COF enhance N 2 reduction via the electron "acceptance–donation" process. The solar conversion of nitrogen to ammonia is a green, sustainable, and promising way to fix nitrogen. However, designing a photocatalyst with high activity, selectivity, and stability for the N 2 reduction reaction (NRR) is challenging because of the slow inert activation of N 2 and competitive hydrogen evolution reaction (HER). Herein, a single metal site anchored to a triazine-based covalent organic framework (Tr-COF) backbone (named TM@Tr-COF; TM = Fe, Co and Ni) is fabricated for high-performance catalytic N 2 reduction. Density functional theory calculations show that the Fe@Tr-COF, Co@Tr-COF and Ni@Tr-COF can effectively activate N 2 and reduce it to NH 3 via the electron "acceptance–donation" process. Meanwhile, the NRR occurs via the enzymatic pathway on the Fe@Tr-COF, Co@Tr-COF and Ni@Tr-COF with a limiting potential of 0.38 V, 0.58 V and 0.54 V, respectively. Furthermore, the anchoring of Fe/Co/Ni on the Tr-COF allows the Tr-COF to be adjusted to the appropriate edge position and visible light-absorption region, indicating that the system may be a promising and efficient photocatalyst. Compared with other competitive reactions, the system exhibits high selectivity for NH 3 production and inhibits competitive HERs. These findings have considerable implications for innovatively designing highly active single-atom catalysts supported by COFs. [ABSTRACT FROM AUTHOR]