Efficiently improving the photocatalytic hydrogen evolution of g-C3N4 by (Pt/MoP) composite co-catalyst with low amount of Pt

g-C3N4 has great potential as metal-free and low-cost photocatalyst. However, its efficiency of photo-excited carriers separation is very low, it needs large amount of Pt (such as 3.0%) to resolve this problem. Here, we designed composite co-catalyst (Pt/MoP) and prepared (Pt/MoP)/g-C3N4. The optimal activity of (Pt/MoP)/g-C3N4 reaches 531.75 mu mol/h/g with 1.0% Pt. Compared with 3.0%Pt/g-C3N4, the activity of (Pt/MoP)/g-C3N4 increased 2 times, whereas the amount of Pt is reduced 3 times. Photoelectrochemistry, surface photovoltage (SPV) and transient photovoltage (TPV) spectra prove (Pt/MoP) can effectively separate photo-excited carriers, thereby improve photocatalyst activity of g-C3N4. Here, MoP acts as electron storage due to the large capacitance, and Pt acts as proton reduction sites. This article gives a method to effectively reduce the amount of noble metal in photocatalysts. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.