Tailoring Schottky Barriers and Active Sites in Bi-metallic Cluster Mesoporous Carbon Nitride Heterostructures nanocomposite for Hydrogen Evolution with In-situ insights

Abstract The advancement of photocatalysis relies on the development of novel hetero-structured materials with unique architectures. In this study, we successfully synthesized a hetero-structured g-C3N4 (GCN) material with a distinctive surface modification. To further enhance its photocatalytic performance, we optimized the Ag-Ni concentration to maximize the active sites for hydrogen evolution reactions. By using systematic physicochemical characterizations and density functional theory (DFT) calculations, we elucidated the pivotal role of graphitic carbon nitride (g-C3N4) in facilitating the formation of an efficient charge transfer channel and promoting the effective generation and separation of photo-generated carriers. From the DFT calculations, we also demonstrated that the Ag-Ni nanoparticles provide more efficient active sites than Ni nanoparticles for water splitting and hydrogen evolution and In-situ TEM exploration. Furthermore, the hetero microstructure consisting of thin g-C3N4 nano scrolls has a crucial role in shortening the migration distance of the carriers, effectively suppressing carrier recombination. Consequently, these extraordinary characteristics resulted in a superior solar light-driven photocatalytic H2 evolution rate of 2507 µmol h− 1 g− 1, surpassing the rate achieved by bulk g-C3N4 by a remarkable 18.6-folds. Moreover, the apparent quantum efficiency of this hetero-structured material reached an exceptional value of 1.6% under a 1.5 G air mass filter.