Pyrolysis-Synthesized g-C3N4/Nb2O5 Nanocomposite for Enhanced Photocatalytic Activity under White LED Light Irradiation

摘要

The design and fabrication of highly active visible-light-driven photocatalysts have been received considerable attention in recent years. However, individual component-based photo- catalysts are limited in their use because of the high recombination of photoinduced carriers and poor chemical stability. Herein, the Z-scheme-originated photocatalytic activ- ity of in-situ deposited Nb2O5 NPs on the plane surface of carbon nitride (g-C3N4) nanosheets (i. e. CN-NbO) heterostruc- tures was studied using a simple thermal pyrolysis method. The as-synthesized photocatalysts distinctly manifested efficient white light-emitting diode (LED) light irradiation toward organic malachite green (MG) dye degradation and photo- catalytic hydrogen generation. The CN-NbO heterostructure showed a faster degradation rate of the MG dye and a higher photocatalytic hydrogen evolution rate. In addition, the plausible Z-scheme photocatalytic mechanism for photocata- lytic hydrogen production under LED light irradiation was discussed. Photoelectrochemcial studies showed that the superior photoactivity of CN-NbO heterostructure is mainly a result of the suitable alignment of the band edge positions, which diminish carrier recombination and facilitate efficient interfacial charge transport at their interface. This study provides an ideal method for in-situ fabrication of novel two dimensional/one dimension-based photocatalysts with high activity and stable performance for photocatalytic hydrogen generation.