用光电流作用谱、光电流电势图等光电化学方法研究了TiO2/聚苯胺复合多孔膜电极在不含氧化还原对和含有不同氧化还原对体系中的光电转换过程.结果说明,TiO2/聚苯胺复合多孔膜电极为双层n-型半导体结构,TiO2多孔膜的禁带宽度为3.2eV,外层聚苯胺膜的禁带宽度为2.88eV.用导电高聚物修饰半导体电极可以使可见光区光吸收增强,光电流明显增加,产生光电流起始波长红移至>600nm,从而提高了宽禁带半导体电极的光电转换效率.
The photon to electricity conversion process of nanoporous TiO 2/PAn film electrode was studied in electrolytes with and without redox couple by using the photocurrent action spectra and potential dependence of photocurrent. It is concluded that the nanoporous TiO 2/PAn film electrode has a structure of duplex n type semiconductor layers. The band gap of PAn film is 2.88eV.The TiO 2 nanoporous film electrode modified by PAn can extend the range of optical absorption into visible and infrared region and effectively increase the photocurrent in the visible and infrared region. The photocurrent threshold shifts to>600nm and conversion efficiency of light to electricity is improved.
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