Photocatalytic C-C coupling and H2 production with tunable selectivity based on ZnxCd1-xS solid solutions for benzyl alcohol conversions under visible light

Abstract

Photocatalytic C-C coupling is a green and sustainable route to produce value-added chemicals. However, the product selectivity is generally non-tunable and there is a lack of an in-depth understanding of the dependence of product selectivity on the band structure of the semiconductor photocatalyst. Here, ZnxCd1-xS solid solutions have been explored for photocatalytic C-C coupling using benzyl alcohol as a typical reactant. The conversion rate of benzyl alcohol and selectivity of C-C coupling products is inherently linked to the solid solution level of ZnxCd1-xS which can be readily tuned. An optimal solid solution level has been found at Zn0.6Cd0.4S (x = 0.6) which delivers a conversion rate of 91.61% and a selectivity of 98.83% for C-C coupling products. These findings not only deepen the understanding on factors that affect product selectivity but also justify the usefulness of solid solutions in tuning the C-C coupling reactions.