Simultaneous Loading of Ni2P Cocatalysts on the Inner and Outer Surfaces of Mesopores P-Doped Carbon Nitride Hollow Spheres for Enhanced Photocatalytic Water-Splitting Activity

Promoting charge separation, constructing active sites, and improving the utilization of metal atoms are very important for the design of efficient photocatalysts. A simultaneous loading of Ni2P cocatalysts on the inner and outer surfaces of mesoporous P-doped carbon nitride hollow nanospheres (PCNHS) to construct a Ni2P@PCNHS@Ni2P photocatalyst is reported. Ni2P cocatalysts loading provides enough active sites on both the inner and outer surfaces for proton reduction, and the formed heterojunctions simultaneously promote the migration and separation of the photogenerated charges on the inner and outer surfaces. The photocatalytic reaction proceeds simultaneously on the inner and outer surfaces of Ni2P@PCNHS@Ni2P, which leads to a significantly improved photocatalytic water splitting performance and enhanced atomic utilization. Notably, the hydrogen evolution rate of Ni2P@PCNHS@Ni2P is 2.4 times higher than that of Pt-loaded PCNHS. The findings guide the design of hollow nanostructured composites with high-boosting photocatalytic performance.