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用光电流作用谱、光电流-电势图和瞬态光电流谱等光电化学方法研究了TiO2多孔膜电极在含不同氧化还原体系的电解质溶液中的光电转换过程.结果说明TiO2多孔股为n-型半导体，其禁带宽度为3.26eV.当在电解质溶液中加入醌二苯酸（BQ／HQ），TiO2多孔膜电极的光电流作用谱形基本与没加氧化还原对时类似。在可见光区的光电流拖尾是由于醌被光激发，然后给出电子到TiO2多孔膜导带而产生阳极光电流.而在电解质溶液中加入Fe（CN）3-6-／4-时，TiO2多孔膜电极的光电流作用谱有明显的改变.除了在小于380nm短波区有光电流峰外，还在400-600nm的可见光区观察到宽的光电流峰，大大增加了光电流转换效率.同时在小于-0.2V下为阳极光电流，在-0.2V～0.3V电势区间为明显阴极光电流，在大于0.3V下可观察到较弱的阳极光电流.当电极电势大于-0.2V时，光电流瞬态谱在开始光照时有一阴极瞬态光电流尖峰，然后转变为阳极稳态光电流.这是因为当电极电势较负时，Fe（CN）4-6与TiO2的电子传递络合物可以吸收光子，光生电子迅速注入TiO2导带，然后还原溶液中的而产生阴极光电流.
The photoelectrochemical conversion of TiO2 porous membrane electrode in electrolyte solutions with different redox systems was studied by means of photo-current spectroscopy, photo-current-potential diagram and transient photo-current spectroscopy. The results showed that TiO2 porous cells were n- Type semiconductor with a forbidden band width of 3.26 eV. When the quinone-diphenyl acid (BQ / HQ) was added to the electrolyte solution, the photocurrent action profile of the TiO2 porous membrane electrode was basically similar to that without the redox couple. The photocurrent in the visible region is tailing due to photo-excitation of the quinone, which gives anodic photocurrent to the conduction band of the TiO2 porous film. When Fe (CN) 3-6- / 4- is added to the electrolyte solution, The photocurrent spectrum of TiO2 porous film electrode obviously changed.Except for the short-wavelength light current peak less than 380nm, a wide photocurrent peak was observed in the visible light region of 400-600nm, which greatly increased the photocurrent conversion efficiency. At the same time, the photocurrent of anodes was less than -0.2V, the cathodic photocurrent was obvious in the potential range of -0.2V ~ 0.3V, and the weak anodic photocurrent was observed at a voltage of greater than 0.3V. When the electrode potential was greater than -0.2V , The photocurrent transient spectrum at the beginning of illumination has a cathode transient photocurrent peak, and then changes to anode steady-state photocurrent.This is because when the electrode potential is negative, the electron transfer between Fe (CN) 4-6 and TiO2 Photonic compounds can absorb photons, photogenerated electrons into TiO2 conduction band, and then restore the solution to produce a cathodic photocurrent.