Graphene quantum dots modified flower like Bi2WO6 for enhanced photocatalytic nitrogen fixation

Graphene quantum dots modified Bi2WO6(GQD/Bi2WO6) composites is applied to photocatalytic N2 fixation. The as-prepared GQD/Bi2WO6 samples showed considerable increase in photocatalytic nitrogen fixation compared to the pure Bi2WO6 and GQD. The results revealed that GQD uniformly placed on the surface of Bi2WO6 and tight junction between the two samples helped to boost the photocatalytic activity. The PL, photocurrent and EIS analyses further demonstrated that the composite had the low recombination rate of photo-generated charges. Photocatalytic nitrogen fixation test indicated that GQD/Bi2WO6 with 10 wt% GQDs exhibited the highest ammonia synthesis rate in the presence of visible light, which is 8.88-fold and 33.8-fold higher than pure Bi2WO6 and GQD. Simultaneously, the GQD/Bi2WO6 sample has high stability. (C) 2019 Published by Elsevier Inc.