酸化亜鉛微粉体層の表面光起電力の圧力依存性

抄録

The surface potential of ZnO powder and ZnO-resin layers was measured as a function of ambient air pressure by the Kelvin method. The surface potential in the dark decrased with decrease of air pressure up to several torr by the desorption of water molecule adsorbed on the surface of ZnO powder. The surface potential of ZnO powder and ZnO-resin layers in the dark agreed with the surface potential of gold metal at a vacuum of 2×10^-4 torr. The surface photovoltage of ZnO powder layer increased linearly with the decrease of air pressure up to 10 torr. The dark decay rate of the surface photovoltage decreased with the decrease of air pressure. For ZnO-resin layer, the ambient air pressure dependence of the surface potential in the dark and under illumination was small compared with that of ZnO powder layer. However, the dark decay rate of the surface photovoltage of ZnO-silicone resin layer depends intensely on ambient air pressure. A visible light quenching phenomenon was observed depending on ambient air pressure for ZnO-silicone resin layer sensitized with rose bengal.