Ag2NCN anchored on Ti3C2Tx MXene as a Schottky heterojunction: enhanced visible light photocatalytic efficiency of rhodamine B degradation

Abstract

The quick charge recombination of light-generated electrons and holes severely restricts the photocatalytic applications of single semiconductors. Here, a straightforward electrostatically driven self-assembly technique was used to construct an Ag₂NCN/Ti₃C₂T_x Schottky heterojunction, which was then used to degrade Rhodamine B (RhB) in the illumination of visible light. The findings from the experiments revealed that as a cocatalyst, Ti₃C₂T_x significantly suppresses the recombination rate and broadens visible absorptivity to improve Ag₂NCN photocatalytic efficiency. The optimized Ag₂NCN/Ti₃C₂T_x (AT2) composite exhibited an outstanding photocatalytic rate in 96 min, with the highest RhB degradation rate (k = 0.029 min⁻¹), which was around fifteen times that of pure Ag₂NCN (k = 0.002 min⁻¹). Furthermore, the trapping-agent experiment showed photogenerated superoxide radicals and holes were the principal active agents inside the photodegradation of RhB. Compared with Ag-based semiconductors, the composite exhibited outstanding photostability, highlighting its excellent potential for application in visible-light photocatalysis.