摘要
用光电流作用谱、瞬态光电流、循环伏安及线性电位扫描法研究了TiO2纳米晶/纳米多孔膜电荷传输特性.结果表明TiO2纳米多孔膜的电荷传输与块体半导体不同.TiO2纳米晶电极的能带不弯曲,电子在导带中可向两个方向流动,电子既可以流向电极内部经由外电路输出.也可以流向电解质溶液被溶液中的受主捕获.在TiO2纳米多孔膜电极中,不仅在负电位区能带边随电位变化,而且在正电位区能带边随电位变化而移动,即带边不钉扎。加入合适的施主可提高光电转换效率.加入受主则在电极溶液界面引起电子的严重损失,降低光电转换效率.
Charge transport properties of Tio2nanoporous film were investigated by electrochem-ical and photoelectrochemical methods. The results show that charge transports in nanoporousfilm are different from that in conventional bulk semiconductors. The electrons have free flowsto both directions, thus the energy bands are unbent, the electron transports are controlled by concentration diffusion inconduction band of TiO2 nanoporous folm. Adding acceptors will causeelectron losses in the interface, band edges move with externally applied bias. adding appropriatedonors will improve photon to current conversion efficiency.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1998年第4期309-314,共6页
Acta Physico-Chimica Sinica
基金
国家自然科学基金
中国科学院化学研究所有机固体实验室开放基金
关键词
纳米晶
纳米多孔膜电极
二氧化钛
电荷传输
TiO_2 nanocrystalline/nanoporous film electrode, Photocurrent action spectra, Charge transport