In-situ one-step preparation of anatase/rutile TiO2(A/R) with oxygen vacancy modification derived from 2D Ti3C2 for enhanced visible-light-driven photodegradation of tetracycline

Abstract

The accumulation of residual tetracycline in water environment is an environmental problem that needs to be solved urgently. As an attractive photocatalyst for antibiotic removal, TiO2 has limited photocatalytic activity due to its low solar light utilization efficiency and low quantum yield. Herein, the oxygen vacancy modified Ti3C2/TiO2(anatase/rutile) (TTO(A/R)) heterojunction photocatalyst was successfully synthesized and regulated by adjusting the hydrothermal oxidation time using Ti3C2 as the metal material and homologous titanium. The TTO(A/R)8 h heterojunction photocatalyst with optimal composition percentage of (Ti3C2) 30.93%, (A-TiO2) 54.58% and (R-TiO2) 14.49% showed the best photocatalytic degradation efficiency of TC, which was increased by 1.5 times compared with commercial P25. Further characterization results indicated that the local states formed by the introduced oxygen vacancy broadened the visible range of TTO(A/R)8 h to ∼700 nm. The separation of photogenerated electrons-holes was highly promoted by biphasic TiO2 and the interface Schottky junction between TiO2 and Ti3C2, which would provide more photogenerated electrons and holes to participate in the photocatalytic reaction. Our research provided a new idea for constructing composite photocatalyst derived from Ti3C2 to treat refractory organic pollutants.