H2O2-reduction synthesized Au nanoparticles anchored on Ti3C2Tx MXene-derived C-TiO2 for high-efficiency photocatalytic performance

Abstract

The effective separation of photogenerated charges is recognized as a critical determinant of semiconductor photocatalytic performance, where charge recombination is primarily attributed to the limited spatial separation distance between localized electron and hole accumulation regions. A novel strategy was proposed for synthesizing Au nanoparticles (NPs) via an H₂O₂ reduction method at room temperature, and an effective structure was designed to enhance photocatalytic activity by anchoring Au NPs onto Ti₃C₂T_x MXene-derived TiO₂ supported on a carbon layer (Au/C-TiO₂). In this structure, photoinduced carriers were generated by TiO₂, and the C layer bridged Au and TiO₂ NPs, acting as an intermediate transfer medium for photoinduced electrons to the Au NPs. The experimental results demonstrated that the recombination of photoinduced carriers was effectively suppressed in this structure, while the light absorption range was significantly extended relative to pure TiO₂. Among all the photocatalysts, the Au/C-TiO₂ composite showed the highest degradation efficiency, with a 1.3-fold increase compared to the C-TiO₂ and a 1.8-fold boost relative to pristine TiO₂. This work proposes a novel strategy to advance the effective separation and accelerated transfer of photoinduced charge carriers, offering innovative pathways for optimizing interfacial charge dynamics in photocatalytic systems.