Visible light photocatalytic property and mechanism of peroxy bond incorporated layered H4Nb6O17 niobate

Abstract

The layered niobium oxide H4Nb6O17 (HNO) crystal has an open layered structure. The H2O2 molecules can enter rapidly into the interlayers of HNO crystal, and coordinate with Nb within NbO6 octahedron to form the peroxy bond intercalated HNO crystal (P-HNO). The introduction of peroxy bond causes the positive shift of the CB minimum of HNO crystal from −0.39 eV to 0.42 eV, resulting in its band gap narrowing from 3.49 eV to 2.68 eV and the improvement of visible light absorption. The photocatalytic investigation indicates that such P-HNO crystal has the visible light photocatalytic performance for RhB dye degradation. Moreover, the trapping experiment indicates that h+ and ▪ are the main active species during the visible light photocatalytic degradation of RhB dye. And the study of photocatalytic degradation mechanism shows that there is a synergy between P-HNO crystal and RhB during the photodegradation of RhB.