Interfacial Optimization of Oxygen-Vacancy-Induced 1d/2d Ceo2 Nanotubes/G-C3n4 Step-Scheme Heterojunction with Enhanced Visible-Light Photocatalysis and Mechanism Insight

Oxygen-vacancy-induced one-dimensional (1D) CeO2 nanotubes (CeNT) has successfully loaded on two-dimensional (2D) graphitic carbon nitride (g-C3N4) by simple methods for investigating the performance of photocatalytic degradation of sewage. The results of characterization analyses have proved that the CeNT are uniformly dispersed on the surface of the g-C3N4 nanosheets. The electron paramagnetic resonance (EPR) spectra signal exhibited the existence of oxygen vacancies in CeNT. Photoluminescence spectra (PL), UV-vis diffuse reflectance spectra (UV-vis DRS) and photoelectrochemical measurements demonstrated that the appropriate amount of CeNT (28 mg) can effectively improve the separation efficiency of photo -generated charge carriers and the photoresponse property of the samples. The rhodamine B (RhB) de-gradation experiments verify the same results that the photocatalytic degradation efficiency of the samples for RhB increased initially, followed by a decreased, meanwhile the degradation activity didn't decrease prominently after four circles. Also, the reactive species trapping experiment indicated that the holes (h(+)) and superoxide radicals (.O-2(-)) played major role in the photocatalytic reaction. Finally, the enhanced photocatalytic performance can be attributed to the synergistic effects of the oxygen vacancies in CeNT and a new charge transfer mechanisms of Step-scheme heterojunction for electron separation, which could provide a new green solution for photocatalytic sewage treatment. (C) 2022 Elsevier B.V. All rights reserved.