Expediting H2 Evolution over MAPbI3 with a Nonnoble Metal Cocatalyst Mo2C under Visible Light

Halide perovskites have been emerging as promising photocatalytic materials for H-2 evolution from water due to their outstanding photoelectric properties. However, the lack of proper surface reactive sites greatly hinders the photocatalytic potential of these fascinating compounds. Here, Mo2C nanoparticles have been anchored onto methylammonium lead iodide (MAPbI(3)) as a nonnoble metal cocatalyst to promote H-2 evolution reactions. The Mo2C nanoparticles have opposite zeta potential with MAPbI(3) thereby electrostatically assembled onto the MAPbI(3) surface, i.e., Mo2C@MAPbI(3). Our results show that the anchored Mo2C nanoparticles have a strong interplay with MAPbI(3) substrate so that photogenerated electrons of MAPbI(3) can be rapidly separated and transferred into Mo2C for further H-2 evolution reactions. Under optimal conditions, Mo2C@MAPbI(3) delivers exceptionally high photocatalytic performance for visible light-driven H-2 evolution that clearly outperforms pristine MAPbI(3) and Pt-deposited MAPbI(3). An apparent quantum efficiency as high as 12.65% at 600 +/- 40 nm has been attained for H-2 evolution, surpassing most of the MAPbI(3)-based photocatalyst reported. These results signify the usefulness and applicability of Mo2C as a new nonnoble metal-based cocatalyst in solar water splitting.

Automated summary

Halide perovskites are promising photocatalytic materials for H-2 evolution, but lack of proper surface reactive sites limits their potential. Anchoring Mo2C nanoparticles onto MAPbI(3) as a cocatalyst enhances H-2 evolution reactions. Mo2C@MAPbI(3) shows strong interplay, leading to efficient electron separation and transfer, achieving high apparent quantum efficiency for H-2 evolution. This study highlights the potential of Mo2C as a nonnoble metal-based cocatalyst in solar water splitting.