Self-assembly of two-dimensional g-C3N4/rGO nanojunctions with enhanced charge separation and transfer for photocatalytic H2 production

Owing to the efficient transfer of charges between layers, two dimensional (2D) hetero-junctions have attracted much attention in the development of photocatalysts. While how to achieve close interface contact between different materials is still a principal problem. In this work, the hydrogen bonding in graphene carbon nitride (CN) is fractured by alkali conditions, and CN is converted into highly dispersed water-soluble nanowires (S-CN). Thereby the self-assembly of S-CN on the rGO nanosheets is realized by the recombination of new hydrogen bonding to construct a 2D heterojunction with intimate interfacial contact. Because of the efficient transfer of charges in composite interface, S-CN/rGO (2%) exhibits an excellent photocatalytic hydrogen production performance, which is 5 times that of CN/rGO (2%). The efficient transportation of charges and photocatalytic mechanism in 2D heterostructure are studied by FTIR, TEM, XPS, i-t and other characterizations. It supplies a new approach for developing novel 2D heterojunction through intermolecular self-assembly.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Due to the efficient transfer of charges, two-dimensional hetero-junctions have gained significant attention in the field of photocatalysts. However, achieving close interface contact between different materials remains a major challenge. In this study, the hydrogen bonding in graphene carbon nitride (CN) was broken down by alkali conditions, leading to the formation of highly dispersed water-soluble nanowires (S-CN). The self-assembly of S-CN on rGO nanosheets was achieved by recombining hydrogen bonding, resulting in a 2D heterojunction with intimate interfacial contact. The S-CN/rGO (2%) composite exhibited excellent photocatalytic hydrogen production performance, surpassing that of CN/rGO (2%) by five times. Characterization techniques such as FTIR, TEM, XPS, and i-t were employed to investigate the efficient charge transportation and photocatalytic mechanism in the 2D heterostructure. This work provides a new approach for developing novel 2D heterojunctions through intermolecular self-assembly.