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 2 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 2 P, Ni 12 P 5 ), are incorporated into a representative MOF, UiO‐66‐NH 2 , for photocatalytic H 2 production. Compared with the parent MOF and their physical mixture, both TMPs@MOF composites display significantly improved H 2 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 2 production. Significantly, the results indicate that Pt is thermodynamically favorable, yet Ni 2 P is kinetically preferred for H 2 production, accounting for the higher activity of Ni 2 P@UiO‐66‐NH 2 than Pt@UiO‐66‐NH 2 .