| 摘要 |
PURPOSE:To obtain a long-term stable optical catalyst with the high efficiency of utilization of optical energy by providing a surface layer on which a material giving the conductivity that differs from the conductivity of a semiconductor formed on a part of the surface of the semiconductor particle is doped. CONSTITUTION:The surface oxide layers of Si particles with n type conductivity are removed by using a diluting etching solution containing hydrogen fluoride, nitric acid, and a small amount of bromine. After said particles are washed by water and dried, they are immersed in the methanol solution f boron oxide and heated in the air. Then the remaining boron oxide is cleaned by using methanol and removed and silicon oxide on the surface is removed using hydrofluoric acid. An optical catalyst 3a is obtained by pulverizing thus obtained Si particles so that their diameter can become approximately a half and making a small amount of platinum or palladium, etc. adhere on the surface. |
