Construction of Bronze TiO2/Ti3C2 MXene/Ag3PO4 Ternary Composite Photocatalyst toward High Photocatalytic Performance

Abstract

Research has demonstrated that the formation of composites of titanium dioxide (TiO2) with silver phosphate (Ag3PO4) through the construction of heterojunctions can expand its light absorption range and suppress the recombination of photogenerated electron–hole pairs, thereby improving the photocatalytic performance. However, this method offers only limited performance improvements, and the composite photocatalysts are costly due to the expensive Ag3PO4. In this study, Ti3C2 MXene, which has good hydrophilicity and excellent electrical conductivity, is first used to form Schottky junction composites with bronze TiO2 (TiO2(B)) via electrostatic self-assembly. Then, Ag3PO4 quantum dots were further formed on the surface of the TiO2(B)/Ti3C2 MXene by in situ self-growth, and Ag3PO4 formed heterojunctions and Schottky junctions with TiO2(B) and Ti3C2 MXene, respectively. Finally, a ternary composite photocatalyst TiO2(B)/Ti3C2 MXene/Ag3PO4 was jointly constructed by these functional junctions. Under the synergistic effect of these functional junctions, the mobility and fast separation performance of photogenerated electron–hole pairs of the composite photocatalyst were significantly improved, the recombination of photogenerated electron–hole pairs was effectively suppressed, and the light absorption performance was enhanced. As a result, the composite photocatalyst exhibited excellent photocatalytic performances.