Electrocatalytic activity of pristine and electrochemically activated SnSe2 nanoplates for the hydrogen evolution reaction

Ab Initio Studies of Electrocatalytic CO2 Reduction for Small Cu Cluster Supported on Polar Substrates

Small Cu clusters are excellent candidates for the electrocatalytic reduction of carbon dioxide (CO2RR), and their catalytic performance is expected to be significantly influenced by the interaction between the substrate and cluster. In this study, we systematically investigate the CO2RR for a Cu3 cluster anchored on Janus MoSX (X = Se, Te) substrates using density functional theory calculations. These substrates feature a broken vertical mirror symmetry, which generates spontaneous out-of-plane polarization and offers two distinct polar surfaces to support the Cu3 cluster. Our findings reveal that the CO2RR performance on the Cu3 cluster is strongly influenced by the polarization direction and strength of the MoSX (X = Se, Te) substrates. Notably, the Cu3 cluster supported on the S-terminated MoSTe surface (Cu3(S)@MoSTe) demonstrates the highest CO2RR activity, producing methane. These results underscore the pivotal role of substrate polarization in modulating the binding strength of reactants and reaction intermediates, thereby enhancing the CO2RR efficiency.

Nanoarchitectonics of g-C3N4 Nanosheets with a AuCu Enhancement Effect for Superior Photo- and Electrochemical Activity

AuCu alloy nanoparticles (NPs) were embedded in superior thin g-C₃N₄ nanosheets by a mechanochemical pre-reaction and subsequent thermal polymerization at high temperature. The introduction of AuCu NPs increased conductivity, decreased the band gap, expended light absorption, and improved the separation and transfer efficiencies of photogenerated electrons and holes. Moreover, the uniform distribution of AuCu NPs in g-C₃N₄ nanosheets is ascribed to the pre-reaction of bulk g-C₃N₄ and metal salts to create activity cites. The adsorption ability in the visible light region was improved due to the plasma effect of Au. AuCu/g-C₃N₄ composites (AuCu/CN-1%) with optimized component ratios revealed the highest transient photocurrent responses, the lowest electrochemical impedance arc radius, and the best photocatalytic H₂ evolution rate of 930.2 μmol g^-1 h^-1. These findings exhibited that loading AuCu bimetallic NPs could efficiently offset some disadvantages of g-C₃N₄ and improve its photocatalytic performances.