二氧化鈦/氧化亞銅 核殼奈米線光電化學電池之研究

Abstract

Solar cells and hydrogen fuel cells have attracted much attention recently because they are the sources of clean energy. Using sun light to decompose water into H2 and O2 has the advantage that light energy is transferred directly into chemical energy and the energy is stored directly in the hydrogen fuel cell. In this thesis we report the study of using TiO2 /Cu2O nanowire array to transfer light energy into chemical energy and store the energy in the hydrogen fuel cell. In our study we found that Au layer plays an important role in the growth of the TiO2 nanowires. Good quality TiO2 nanowires can be grown when a thin layer of Au was sputtered on top of a Ti (99.7%) and with the nanowires grown at high temperature using Vapor-Liquid-Solid method. The electrochemical deposition of Cu2O films was conducted in an alkaline electrolyte solution with TiO2 and Cu as working electrode and Cu2O oxide can be deposited on TiO2 nanowires by applying suitable voltage. We found that when the TiO2/Cu2O nanowire array is exposed to light illumination, the photocurrent generated in the TiO2/ Cu2O core-shell nanowire array increased seven times as compared with the photocurrent generated by the bare TiO2 nanowirarray. This result is attributed to the enhanced light absorption of TiO2/ Cu2O nanowires and the electron-hole separation due to the type-II band alignment of the TiO2/ Cu2O heterostructure. Our results indicate that TiO2/ Cu2O nanowire array is a promising system in making hydrogen fuel cell.