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Initially, CoNiSx is synthesized on the graphdiyne (GDY) surface through a precipitation method, followed by the straightforward physical stirring approach to attach CoNiSx/GDY to the maple leaf CdS. This synthesis method significantly mitigates the accumulation of CoNiSx/GDY and concurrently augments the count of sites that are active for generating hydrogen. This three‐phase composite demonstrates exceptional performance in the area of photocatalytic hydrogen production, achieving a hydrogen evolution rate of 15.37 mmol·h−1 g−1. The employment of various characterization methodologies and density functional theory calculations have demonstrated the formation of a Z‐scheme heterojunction forms between GDY and CdS. This discovery indicates that the combination of GDY and CdS markedly improves the photogenerated carrier separation capability of the composite catalyst. The cocatalyst CoNiSx loaded on GDY effectively accelerates the electron transfer from the conduction band of GDY, thereby reducing the photogenerated carrier complexation of GDY. This phenomenon results in an increased quantity of photogenerated electron holes engaged in the redox reaction, ultimately achieving exceptional photocatalytic performance. [ABSTRACT FROM AUTHOR]

The reaction mechanism of B4C synthesis as yet remains unclear due to the lack of sufficient thermodynamic investigation, which limits the large‐scale controllable production of B4C ceramic material. In this paper, thermodynamic investigation of B4C synthesized by carbothermal reduction was calculated at atmospheric pressure over a wide temperature range (1500‐2500 K) coupled with the effects of pressure on B4C synthesis. Besides, predominance diagrams for B–C–O system at different temperatures and pressures were further established. Upon thermodynamic results, reaction mechanism was proposed and then verified by the synthesis experiment of B4C at desired temperatures. The thermodynamic investigation indicates that B4C may be synthesized by the reactions of C with liquid B2O3 (LS mechanism) or gaseous B2O2 (VS mechanism). At low temperature (~1823 K), B4C is polyhedral shape via LS mechanism, while two‐dimensional flake‐like B4C is synthesized by VS mechanism at high temperature (2123 K~). The obtained two types of B4C verify the accuracy of thermodynamic results. This study is instructive for the optimization of temperature, pressure for large‐scale controllable production of B4C ceramic material. [ABSTRACT FROM AUTHOR]

Metal coordination polymers are organometallic frameworks in which a metal and an organic ligand are linked via a dative bond. The material in question exhibits ultra-high porosity, large specific surface area, and abundant active sites, which can be customised in terms of morphology, size, and electronic structure through rational design. Graphdiyne, a novel two-dimensional carbon allotrope, boasts structural stability and enhanced electrical conductivity due to its hybridization of sp 2 and sp carbons. A metal-organic framework of Co (MOF-67) was synthesized via hydrothermal synthesis. The introduction of polyvinyl pyrrolidone (PVP) served as a structural regulator and surfactant to obtain a more active metal coordination polymer (Co-MCPS). PVP, in its dual role, significantly amplified the catalytic performance of metal coordinate polymers, as demonstrated in a number of experiments. The incorporation of GDY onto the surfaces of MOF-67 and Co-MCPS induced an electron-rich isolation layer, which could effectively sequester oxidation sites, thereby enhancing the rate of charge carrier separation and hydrogen precipitation evolution efficiency.