Insight into the Activity and Stability of RhxP Nano-Species Supported on g-C3N4 for Photocatalytic H2 Production

Transition-metal phosphides have been demonstrated as cocatalysts with great promise for photocatalytic H 2 production materials, but the insurmountable issue remains maintaining outstanding stability while achieving high photocatalytic efficiency. Herein, the rhodium phosphide (RhP x ) nanospecies as cocatalyst is firmly mounted on graphitic carbon nitride (g-C 3 N 4 ) nanosheets to realize the improved activity and stability for photocatalytic H 2 production. The maximum H 2 production rate over RhP x /g-C 3 N 4 driven by visible light diplays a 5.6-fold improvement compared with Pt/g-C 3 N 4 . Meanwhile, the apparent quantum efficiency of 18.4% is achieved at a fixed wavelength of 420 nm that far exceeds the reported g-C 3 N 4 modified with other single-transition-metal phosphides. Particularly, RhP x /g-C 3 N 4 can maintain consistently stable H 2 production when enduring over 25 cyclic reactions with a total of 100 h. The deep insight into the modification effect of RhP x nanospecies reveals that it dramatically facilitates migration and separation of photoinduced electron–hole pairs and heightens interaction at the heterointerfaces between RhP x nanospecies and g-C 3 N 4 nanosheets. This contribution extends the broad potential application of transition-metal phosphides as cocatalysts in the photocatalytic conversion from solar to hydrogen energy.