Surface plasmon resonance improved photocatalytic activity of Au/TiO2 nanocomposite under visible light for degradation of pollutants

The development of nonprecious and highly efficient photocatalyst by a green technique is highly desirable for environmental remediation. Herein, gold nanoparticles (Au Nps) have been successfully loading on the nanoparticle TiO2 surface by a deposition-precipitation (DP) method. The optimized amount of 3Au/TiO2 nanocomposite used for the degradation of toxic pollutant shows 36-time photo-activity improvement compared to the pure TiO2. According to the experimental results, the study confirmed that the prepared Au/TiO2 nanocomposite material has excellent visible light photo-activity. This is due to the modification of Au surface plasmon resonance (SPR) and its catalytic function which leads to the expansion of visible light response, and the transfer of electrons from SPR-Au to TiO2 enhances the charge separation nanocomposite. In addition, the as-prepared nanocomposite exhibits best stability; even after five cycles, no serious deactivation was observed. Besides, the main active species involved during photocatalytic degradation were confirmed through trapping experiment that super oxide radicals are the leading species for the 2,4-DCP degradation. It is expected that this work would provide a reasonable path to perceptibly improve the photocatalytic activity of TiO2-based photocatalyst for the environmental remediation.