Multifunctional Ni nanoparticles decorated SiC nanofibers/g-C3N4 nanosheets heterojunctions for drastically increased LED-light-driven hydrogen generation

The development of hydrogen (H2) production photocatalyst with low cost, non-precious metal and high-activity for commercial application is a long-term target and challenge. In this work, novel silicon carbide (SiC) nanofibers/graphitic carbon nitride (g-C3N4) nanosheets (SiC/CNNS) decorated via multipurpose nickel (Ni) nanoparticles were prepared by an easy heat treatment followed by hydrothermal method. The tight Ni interface layers as cocatalyst and electron transfer mediator can significantly enhance the H2 production property over SiC/CNNS nanoheterojunctions under light-emitting diode (LED) illumination. The optimal Ni/SiC/CNNS with a mass fraction of 10% Ni loading shows the most superior H2-generation rate of 6183 mu mol gxfffd; 1h- 1, which is approximately 53, 3 and 227 times compared to CNNS, 10 %Ni/CNNS and SiC/CNNS, respectively. The metallic Ni nanoparticles play the leading and multifunctional roles in improving photocatalytic activity, including collecting the photo-generated electrons efficiently, transferring and separating the charge carriers rapidly, facilitating the H2-production kinetics and decreasing the overpotentials of surface reactions for H2-production. It is highly expected that the multipurpose and non-precious metal cocatalyst to form tight interface layers can supply a simple and universal strategy to design high-efficiency cocatalyst-semiconductor-semiconductor photocatalysts for H2 production.