title: A new dielectric ta-C film coating of Ag-nanoparticle hybrids to enhance TiO2 photocatalysis.
abstract: We have demonstrated a novel method to enhance TiO₂ photocatalysis by adopting a new ultrathin tetrahedral-amorphous-carbon (ta-C) film coating on Ag nanoparticles to create strong plasmonic near-field enhancement. The result shows that the decomposition rate of methylene blue on the Ag/10 Å ta-C/TiO₂ composite photocatalyst is ten times faster than that on a TiO₂ photocatalyst and three times faster than that on a Ag/TiO₂ photocatalyst. This can be ascribed to the simultaneous realization of two competitive processes: one that excites the surface plasmons (SPs) of the ta-C-film/Ag-nanoparticle hybrid and provides a higher electric field near the ta-C/TiO₂ interface compared to Ag nanoparticles alone, while the other takes advantage of the dense diamond-like ta-C layer to help reduce the transfer of photogenerated electrons from the conduction band of TiO₂ to the metallic surface, since any electron transfer will suppress the excitation of SP modes in the metal nanoparticles.
authors.affiliation: Department of Applied Physics, Zhejiang University of Technology, Xiaoheshan, Hangzhou 310023, People's Republic of China. National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Fanxin
authors.initials: F
authors.lastname: Liu
authors.forename: Chaojun
authors.initials: C
authors.lastname: Tang
authors.forename: Zhenlin
authors.initials: Z
authors.lastname: Wang
authors.forename: Chenghua
authors.initials: C
authors.lastname: Sui
authors.forename: Hongtao
authors.initials: H
authors.lastname: Ma