摘要
The photo-generated charge property of TiO 2 nanoparticles annealed at different temperatures was studied by the field induced surface photovoltage spectrum (FISPS) technique. The powder of TiO 2 was prepared and annealed at 400, 600 and 800 ℃, respectively. The crystalline of TiO 2 transformed from anatase to rutile with the annealing temperature increasesing. And the photo-generated charges property of TiO 2 behaves differently after it was annealed at different temperatures. When the powder was annealed at 400 ℃, the particle size is so small that the energy band can not be formed completely, so the bound exciton state was formed when it was illuminated by the proper incident light, and it inverse antisymmetrically under external field for locatization effect. While, the powder was annealed at 600 ℃, the surface phtovoltaic response presents the characteristics of homojunction for different crystalline interfaces. After being annealed at 800 ℃, the energy band was formed completely and the larger particle size(36 nm) was got. Consequently, a band for the dissociation of free exciton emerged in the band edge of the surface photovotaic response distinguished from the band-band transition, and the direction of the photovoltaic response resulted from the free excition is consistent with the external field, that is positive under positive field, and it inverse symmetrically under external field.
The photo-generated charge property of TiO 2 nanoparticles annealed at different temperatures was studied by the field induced surface photovoltage spectrum (FISPS) technique. The powder of TiO 2 was prepared and annealed at 400, 600 and 800 ℃, respectively. The crystalline of TiO 2 transformed from anatase to rutile with the annealing temperature increasesing. And the photo-generated charges property of TiO 2 behaves differently after it was annealed at different temperatures. When the powder was annealed at 400 ℃, the particle size is so small that the energy band can not be formed completely, so the bound exciton state was formed when it was illuminated by the proper incident light, and it inverse antisymmetrically under external field for locatization effect. While, the powder was annealed at 600 ℃, the surface phtovoltaic response presents the characteristics of homojunction for different crystalline interfaces. After being annealed at 800 ℃, the energy band was formed completely and the larger particle size(36 nm) was got. Consequently, a band for the dissociation of free exciton emerged in the band edge of the surface photovotaic response distinguished from the band-band transition, and the direction of the photovoltaic response resulted from the free excition is consistent with the external field, that is positive under positive field, and it inverse symmetrically under external field.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2003年第12期2282-2284,共3页
Chemical Journal of Chinese Universities
基金
国家自然科学基金 (批准号 :2 0 2 73 0 2 7
2 0 2 770 15 )
吉林大学纳米专项 (重点 )基金资助
