Highly efficient and selective photocatalytic dehydrogenation of benzyl alcohol for simultaneous hydrogen and benzaldehyde production over Ni-decorated Zn0.5Cd0.5S solid solution

摘要

Photocatalytic conversion of solar energy into hydrogen and high value-added fine chemicals has at-tracted increasing attention. Herein, we demonstrate an efficient photocatalytic system for simultane-ous hydrogen evolution and benzaldehyde production by dehydrogenation of benzyl alcohol over Ni-decorated Zn0.5Cd0.5S solid solution under visible light. The photocatalytic system shows an excellent hydrogen production rate of 666.3 μmol h^-1 with high stability. The optimal apparent quantum yield of 52.5% is obtained at 420 nm. This noble-metal-free photocatalytic system displays much higher activity than pure Zn0.5Cd0.5S and Pt-loaded Zn0.5Cd0.5S solid solution. Further studies reveal that the metallic Ni nanocrystals play an important role in accelerating the separation of photogenerated charge carriers and the subsequent cleavage of α-C–H bond during dehydrogenation of benzyl alcohol.