Z-scheme g-C3N4/Fe2O3 for efficient photo-oxidation of benzylamine under mild conditions

Abstract

As an important intermediate, imine is widely used in industrial chemistry. The photocatalytic oxidation of amines to form imines is a green and economical method. But it remains a challenge for the efficient transformation under mild conditions. Herein, a Z-scheme carbon nitride (CM)-Fe2O3 heterojunction photocatalyst was synthesized by in-situ preparation of Fe2O3 nanoparticles on two-dimensional CM nanosheets. The as-prepared catalyst exhibited efficient photocatalysis activity in selective oxidation of benzylamine to N-benzylidene benzylamine. Under ambient air and room temperature, the selectivity and conversion rate both can reach 99.9%, and the corresponding turnover frequency value reaches up to 9.99 mmol g−1 h−1, superior to the most of heterogeneous photocatalysts reported in previous literatures. The excellent catalytic activity of the modified CM material may be due to the enhanced absorption of visible light and the improved photogenerated carrier separation and migration rate, and the Z-scheme mechanism also retains the strong oxidation and reduction ability of the composite material. This work will provide a promising and practical method to promote the photocatalytic conversion of solar-driven organics.