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On the other hand, the accessible multiple oxidation states of reactive Cu elements (Cu SP 0 sp , Cu SP I sp , Cu SP II sp , and Cu SP III sp ) within Cu-based catalysts can enable targeted catalytic reactions that proceed via both single- and multi-electron transfer. Dang et al. [[5]] synthesized self-supported Cu/Cu SB 3 sb P nanoarrays through a low-temperature phosphidation process, which were directly grown on the surfaces of Cu nanosheets from Cu/CuO nanoarrays precursor. Compared with the Cu(111) surface, the Cu-skin Cu SB 3 sb Au(111) surface showed higher stability of O SB 2 sb adsorption and a lower dissociation energy barrier of the adsorbed O SB 2 sb . [Extracted from the article]

Generating different types of defects in heterogeneous catalysts for synergetic promotion of the reactivity and selectivity in catalytic reactions is highly challenging due to the lack of effective theoretical guidance. Herein, we demonstrate a facile strategy to introduce two types of defects into the CuO-ZnO model catalyst, namely oxygen vacancies (OVs) induced by H2 partial reduction and localized amorphous regions (LARs) generated via the ball milling process. Using industrially important Rochow-Müller reaction as a representative, we found OVs predominantly improved the target product selectivity of dimethyldichlorosilane, while LARs significantly increased the conversion of reactant Si. The CuO-ZnO catalyst with optimized OVs and LARs contents achieved the best catalytic property. Theoretical calculation further revealed that LARs promote the generation of the Cu3Si active phase, and OVs impact the electronic structure of the Cu3Si active phase. This work provides a new understanding of the roles of different catalyst defects and a feasible way of engineering the catalyst structure for better catalytic performances. [ABSTRACT FROM AUTHOR]

The synergistic effects between Co NPs and pyridinic nitrogen of Co/CN-x catalysts was the key to realize the base-free oxidation of mercaptans to their corresponding disulfides by decreasing the energy barrier for the deprotonation of mercaptans. [Display omitted] The oxidation of mercaptans under mild and base-free conditions is of vital importance in terms of economy and environment for petroleum processing industry. Here, we developed a series of MOF-derived cobalt-based nitrogen-doped (N -doped) carbon (Co/CN-x) catalysts for the base-free catalytic oxidation of mercaptans. The optimal Co/CN-900 showed excellent catalytic activity for the oxidation of mercaptans under base-free conditions, yielding complete conversion of various mercaptans and > 99.0% selectivity of disulfides. The high performance can be contributed to the advantages of hierarchical pore structure for the diffusion and migration of substrates, self-carrying alkalinity for the formation of mercaptide anion, abundant active Co sites for catalytic oxidation of mercaptans as well as the synergistic effects between the Co nanoparticles (NPs) and N -doped carbon supports. Furthermore, a possible mechanism for base-free catalytic oxidation of mercaptans over Co/CN-x catalysts is proposed based on a set of control experiments and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]