Fabrication of graphitic-C3N4 quantum dots/graphene-InVO4 aerogel hybrids with enhanced photocatalytic NO removal under visible-light irradiation

A new 3D aerogel of CNQDs/GO-InVO4 (CNQDs = graphitic C3N4 quantum dots, GO = graphene oxide) with porous layered structure is fabricated successfully. The stable and recyclable macro-material is found to be highly suitable for practical application. CNQDs with an average diameter of 3.0 nm are prepared through the exfoliation of bulk g-C3N4 step by step, and are decorated on the surface of GO uniformly by electrostatic, ππ stacking and hydrogen-bonding interactions. The CNQDs/GO are wrapped tightly around cubic InVO4, resulting in the immediate formation of a 3D aerogel with a heterostructure. The synergistic heterojunction exhibit a powerful photocatalytic effect for the removal of NO at the ppb-level (600 ppb) under visible-light irradiation, with a maximum efficiency up to 65%. A Z-scheme photocatalytic mechanism is proposed based on ESR experiments and calculation of the energy bands.