PHOTOCHEMICAL REACTION CONTROLLED BY PHOTOCHEMICAL DIODE AND ITS APPLICATION TO FIXATION OF CARBON DIOXIDE

本研究的结果总结如下。(1)由n-TiO_2 /Ti组成的产物可分离的光化学二极管表现为光活性晶片。在KHCO_8水溶液中，氙灯照射光化学二极管n-TiO_2表面，分别诱导Ti金属和n-TiO_2半导体产生氢和氧，而Cu沉积在Ti金属上，除了在Cu金属上产生一氧化碳外，还产生甲烷和乙烯等碳氢化合物。(2)我们用光化学二极管对不同Cu/Ag原子比的n-TiO_2/Ti/Cu-Ag体系进行了CO_2的选择性还原研究。通过在Ti/Cu表面电沉积少量Ag，发现CO_2还原的主要产物是乙烯，而不是甲烷。(3)我们还发现，石墨层间化合物与铜和铁的氯化物，敏化的光照射的氙灯，产生光电流和光电压。

The results of this research are summarized as follows.(1) The product-separable photochemical diode composed of n-TiO_2 /Ti was manifested as photoactive wafers. A Xe-lamp illumination on a n-TiO_2 surface of photochemical diode in an aqueous solution of KHCO_8 induced the production of hydrogen and oxygen en Ti metal and n-Ti0_2 semiconductor, respectively, while by a deposition of Cu onto Ti metal hydrocarbons such as methane and ethylene were produced in addition to carbon monoxide on Cu metal.(2) We found the selective reduction of CO_2 using the photochemical diode of the system n-TiO_2/Ti/Cu-Ag with various atomic ratios of Cu to Ag on the surface of Ti. By electrodeposition of a small amount of Ag onto Ti/Cu surface, ethylene was a predominant reduction product from CO_2 rather than methane.(3) We also found that graphite intercalation compounds with copper and iron chlorides, were sensitized by light illumination of a Xe-lamp, generrating photocurrent and photovoltage.