Fabrication of Au-Ag@TiO2 ternary core-shell nanostructures with enhanced sunlight photocatalytic activity

In this work, Au loaded Ag@TiO2 ternary core-shell structures (Au-Ag@TiO2) were synthesized by a two-step method in mild conditions. The Ag nanoparticles existed as cores in the inner layer and the Au nanoparticles decorated in the outer layer. The greatly improved sunlight absorption performance is due to the LSPR of Au nanoparticles, while the Ag nanoparticles mainly serve as the electron traps to prevent charge recombination. The photocatalytic activity of the as-prepared Au-Ag@TiO(2)was evaluated by photo-degradation of MO under artificial sunlight illumination. And the 1.5%Au-Ag@TiO2 ternary core-shell particles showed the highest photo degradation efficiency, which was about 4 and 1.6 times higher than that of the pristine TiO2 and Ag@TiO2 particles. The main active species that contributed to the reaction were proved to be holes (h+) and superoxide anions (O-2(-)). These proposed Au-Ag@TiO2 ternary core-shell particles are promising for potential applications in environmental remediation and energy conversion. (C) 2022 Elsevier B.V. All rights reserved.