Tubular g-C3N4 coupled with lanthanide oxides Yb2O3 as a novel bifunctional photocatalyst：Enhanced photocatalytic NO removal and H2 evolution, dual regulation and reaction pathway

Abstract

The modification of graphite carbonitride (g-C3N4) is beneficial to increase its specific surface area and high quantum efficiency, thus improving its activity. Herein, the Yb2O3/g-C3N4 composites were adjusted through dual regulation synergistically (nanostructure design of g-C3N4 and addition of lanthanide oxides Yb2O3) to improve the photocatalytic performance of hydrogen production and NO removal simultaneously. The as-prepared 1% Yb2O3/tubular g-C3N4 could efficiently promote the photocatalytic hydrogen evolution (4071.763 μmol·g−1·h−1) and NO removal performance (54.20%), which was approximately 8.85 times and 32.01% higher respectively than that of bulk g-C3N4 prepared by melamine (g-C3N4-M). The formation process of·O2- and·OH radicals and the oxidation process of NO had been systematically studied through ESR and in-situ DRIFTS, which proved that the coupling of tubular g-C3N4 with Yb2O3 had a positive effect. This work provided a novel strategy for dual regulation (adjust morphology and metal oxide introduction) synergistically design of bifunctional photocatalysts to enhance H2 production and NO removal simultaneously.