No abstract

Graphite carbon nitride (g-C 3 N 4 ) has become an emerging metal-free photocatalyst and attracted the attention of researchers. However, pure g-C 3 N 4 (PCN) prepared by traditional thermal condensation polymerization has a low polymerization of heptazine ring chains and a large number of charge recombination centers, which hinder in-plane charge transport, leading to undesirable photocatalytic performance. Herein, PCN fabrication by thermal treatment with ammonium oxalate monohydrate was performed to produce highly dispersed porous g-C 3 N 4 nanosheets, and the integrity of their in-plane heptazine ring chains was successfully improved without introducing heteroatoms. Electron paramagnetic resonance and 13 C nuclear magnetic resonance analyses revealed significantly increased electron density and delocalization of the π-conjugated structure. The obtained samples exhibited acceptable stability and photocatalytic activity, and the hydrogen reduction rates without and with the Pt co-catalyst were 11.2 and 5.3 times that of PCN.

Traditional synthesis approaches of bismuth nanoparticles decorated carbon nitride (C3N4) materials suffers from the complex synthesis process and the addition of surfactant, which is not conducive to environmental protection. To...