Enhancing photocatalysis in SrTiO3 by using Ag nanoparticles: A two-step excitation model for surface plasmon-enhanced photocatalysis.
Surface plasmon (SP)-enhanced ultraviolet and visible photocatalytic activities of SrTiO3 (STO) are observed after incorporating Ag nanoparticles (Ag-NPs) on STO surfaces. A two-step excitation model is proposed to explain the SP-enhanced photocatalysis. The point of the model is that an electron at the valence band of STO is first excited onto the Fermi level of Ag-NP by the SP field generated on the Ag-NP, and then injected into the conduction band of STO from the SP band, leaving a hole at the valence band of STO. A full redox catalytic reaction at the surface of STO is then available. For Ag-NP incorporated STO, up-converted and inter-band photoluminescence emissions of STO are observed, and nonlinear evolutions of photocatalytic activity with illumination light powers are found. Furthermore, near infrared photocatalysis is detected. These results support the proposed model.
Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433, China.
Lei
L
Ma
Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433, China.
Tao
T
Sun
Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433, China.
Hua
H
Cai
Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433, China.
Zhi-Quan
ZQ
Zhou
Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433, China.
Jian
J
Sun
Department of Optical Science and Engineering, and Shanghai Ultra-Precision Optical Manufacturing Engineering Center, Fudan University, Shanghai 200433, China.
Ming
M
Lu