The TiO 2 nanoparticle thin films have been sensitized in situ with CdS nanoparticles. The SPS measurement showed that large surface state density was present on the TiO 2 nanoparticles and the surface state can be ef...The TiO 2 nanoparticle thin films have been sensitized in situ with CdS nanoparticles. The SPS measurement showed that large surface state density was present on the TiO 2 nanoparticles and the surface state can be efficiently decreased by sensitization as well as selecting suitable heat treatment. Both the photocurrent response and the charge recombination kinetics in TiO 2 thin films were strongly influenced by trapping/detrapping of surface states. The slow photocurrent response of TiO 2 nanoparticulate thin films upon the illumination was attributed to the trap saturation effects. The semiconductor sensitization made the slow photoresponse disappeared and the steadystate photocurrent value increased drastically, which suggested that the sensitization of TiO 2 thin films with CdS could get a better charge separation and provide a simple alternative to minimize the effect of surface state on the photocurrent response.展开更多
The ordered two dimensional arrays of uniform copolymer microspheres had been fabricated on a substrate by the liquid capillary meniscus attraction force method. Thin aluminium film was deposited on the latex monolaye...The ordered two dimensional arrays of uniform copolymer microspheres had been fabricated on a substrate by the liquid capillary meniscus attraction force method. Thin aluminium film was deposited on the latex monolayer through vacuum evaporation. After ultrasonic etching and dissolving of polymer spheres a surface with features remained. Different patterings of net, islands and separate spots can be obtained by controlling the ultrasonic treatment time. The interaction among the metal, microspheres and the substrate as well as its effect on the micropatternings has been discussed.展开更多
文摘The TiO 2 nanoparticle thin films have been sensitized in situ with CdS nanoparticles. The SPS measurement showed that large surface state density was present on the TiO 2 nanoparticles and the surface state can be efficiently decreased by sensitization as well as selecting suitable heat treatment. Both the photocurrent response and the charge recombination kinetics in TiO 2 thin films were strongly influenced by trapping/detrapping of surface states. The slow photocurrent response of TiO 2 nanoparticulate thin films upon the illumination was attributed to the trap saturation effects. The semiconductor sensitization made the slow photoresponse disappeared and the steadystate photocurrent value increased drastically, which suggested that the sensitization of TiO 2 thin films with CdS could get a better charge separation and provide a simple alternative to minimize the effect of surface state on the photocurrent response.
文摘The ordered two dimensional arrays of uniform copolymer microspheres had been fabricated on a substrate by the liquid capillary meniscus attraction force method. Thin aluminium film was deposited on the latex monolayer through vacuum evaporation. After ultrasonic etching and dissolving of polymer spheres a surface with features remained. Different patterings of net, islands and separate spots can be obtained by controlling the ultrasonic treatment time. The interaction among the metal, microspheres and the substrate as well as its effect on the micropatternings has been discussed.