Identification of Photoexcited Electron Relaxation in a Cobalt Phosphide Modified Carbon Nitride Photocatalyst

Transition metal phosphides have been recognized as efficient co-catalysts to boost the activity of semiconductor photocatalysts. However, a rigorous and quantitative understanding is still be developed about how transition influence photoexcited electron dynamics. Here, we present nanosecond time-resolved transient absorption spectroscopy (TAS) study dynamics in carbon nitrides (g-C3N4) before after Co and/or P modifications. Our spectroscopic showed that or lowered initial density, whereas they promoted relaxation g-C3N4, with their half-life times (t50%) 2.5 1.8 ns, respectively. The formation CoP co-catalyst compound (t50%=2.8 ns) without significantly lowering charge separation efficiency. Density functional theory (DFT) calculations were undertaken explore underlying fundamental reasons further predicted CoP, compared modification, better facilitates transfer from g-C3N4 reactants.