Integrating plasmonic nanoparticles with TiO₂ photonic crystal for enhancement of visible-light-driven photocatalysis.
Aimed at enhancing photocatalysis through intensifying light harvesting, a new photocatalyst was fabricated by infiltrating Au nanoparticles into TiO(2) photonic crystals (TiO(2) PC/Au NPs). Scanning electron microscopy (SEM) and transmission electron microscope (TEM) images showed that the Au NPs with average diameter around 15 nm were dispersed uniformly into the porous TiO(2) material. The results of the transmittance spectra demonstrated that the light absorption by Au NPs was amplified after they were infiltrated into TiO(2) 240, which was fabricated from 240 nm polystyrene spheres. In the photocatalytic experiments of 2,4-dichlorophenol degradation under visible light (λ > 420 nm) irradiation, the kinetic constant using TiO(2) 240/Au NPs was 2.3 fold larger than that using TiO(2) nanocrystalline/Au NPs (TiO(2) NC/Au NPs). The excellent photocatalysis benefited from the cooperatively enhanced light harvesting owing to the localized surface plasmon resonance of Au NPs, which extended the light response spectra and the photonic effect of the TiO(2) 240 which intensified the plasmonic absorption by Au NPs. The hydroxyl radicals originated from the electroreduction of dissolved oxygen with photogenerated electrons via chain reactions were the main reactive oxygen species responsible for the pollutant degradation.
Key Laboratory of Industrial Ecology and Environment Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
Ying
Y
Lu
Hongtao
H
Yu
Shuo
S
Chen
Xie
X
Quan
Huimin
H
Zhao
D002384:Catalysis; D002733:Chlorophenols / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D055668:Photochemical Processes; D056951:Photoelectron Spectroscopy; D011137:Polystyrenes; D014025:Titanium / Q000737:chemistry*
D002733:Chlorophenols; D011137:Polystyrenes; C009495:titanium dioxide; D017665:Hydroxyl Radical; D006046:Gold; D014025:Titanium; C004762:2,4-dichlorophenol; D010100:Oxygen