Incorporating Transition-Metal Phosphides Into Metal-Organic Frameworks for Enhanced Photocatalysis.

Metal-organic frameworks (MOFs) have been shown to be an excellent platform in photocatalysis. However, to suppress electron-hole recombination, a Pt cocatalyst is usually inevitable, especially in photocatalytic H production, which greatly limits practical application. Herein, for the first time, monodisperse, small-size, and noble-metal-free transitional-metal phosphides (TMPs; for example, Ni P, Ni P ), are incorporated into a representative MOF, UiO-66-NH , for photocatalytic H production. Compared with the parent MOF and their physical mixture, both TMPs@MOF composites display significantly improved H production rates. Thermodynamic and kinetic studies reveal that TMPs, behaving similar ability to Pt, greatly accelerate the linker-to-cluster charge transfer, promote charge separation, and reduce the activation energy of H production. Significantly, the results indicate that Pt is thermodynamically favorable, yet Ni P is kinetically preferred for H production, accounting for the higher activity of Ni P@UiO-66-NH than Pt@UiO-66-NH .