2D/2D Boron/g-C3N4 Nanosheet Heterojunction Boosts Photocatalytic Hydrogen Evolution Performance

Photocatalysis clean hydrogen production is a modern technology for simultaneously addressing and solving energy and environmental issues, of which the most critical part is to develop a highly efficient photocatalyst. In this work, we rationally designed and synthesized a metal-free 2D/2D boron/g-C3N4 nanosheet heterojunction (B-CN) through an electrostatic self-assembly thermal induction combined with ultrasound-assisted technology. The optimized photocatalyst 3.0B-CN possesses a hydrogen generation rate 35 times that of g-C3N4, which provided an impressive H2 evolution photocatalytic activity. The tight heterojunction architecture via the coupling of two-dimensional boron nanosheets and g-C3N4 nanosheets realizes the enhanced visible light absorption, the increasing carrier concentration, and the rapid transfer of interfacial charge and thus hinders the electron–hole recombination. The coupling of two 2D metal-free nanosheet materials for constructing a 2D/2D layered heterojunction in our work offers pioneering tactics for the design and synthesis of green nonmetal 2D photocatalytic HER materials in the future.