Surface photovoltage spectrum (SPS) and field-induced surface photovoltage spectrum (FISPS) are valuable techniques for the determination of pn conduction type of organic semiconductors. Here, conduction characters of azo pigment films composed of pure 4,4′-2-[N-( -hydroxyl)naphthyl]azodiphenyl (A) and 4,4′-2-{N-[ -hydroxyl-γ-(p-nitroanilino)naphthyl]}azodiphenyl (B) as well as A doped with I 2 vapor (AI 2 ) and B doped with NH 3 gas (BNH 3 ) were explored by means of these techniques. The results of the exploration show that film A has n-type character and film B p-type character. On the basis of the reverse photovoltaic properties, films AI 2 and BNH 3 were judged to be characteristic of p-type and n-type conduction, respectively. It appears that a group rich in electrons, either an electrophobic substituent (naphthanol) at the end side of the azo pigment molecule (A) or a dopant (NH 3 ), bestows the azo pigments with n-type character, whereas an electrophilic group, such as the substituent (p-nitroanilino) connected to azo pigment molecules (B) and I 2 , gives them p-type character. The phenomena are fully discussed based on the energy band modes of the Fermi levels of these materials.

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摘要: 以掺氟 SnO2 (FTO)导电玻璃为基底, 采用水热法制备了 ZnO 纳米棒阵列. 通过 In(NO3)3水溶液水洗的 方法, 合成了 In2O3敏化 ZnO 纳米棒阵列光催化剂. 采用场发射扫描电子显微镜(FESEM), X 射线能谱(EDX), X 射线衍射(XRD)及紫外-可见漫反射光谱(UV-Vis DRS)对样品的形貌、 结构、 组成、 晶相等进行一系列的表征. 以 罗丹明 B (RhB)为目标降解物, 探究了 In2O3 敏化 ZnO 纳米棒阵列光电催化活性. 采用场诱导表面光伏技术 (FISPV)研究了不同含量的 In2O3敏化 ZnO 纳米棒阵列在光照射下的光生电荷行为. 结合电化学工作站检测不 同样品的光电流, 随着 In2O3敏化量的改变, 光电流和开路电压也随之改变. 并探讨了 In2O3敏化 ZnO 纳米棒阵 列光生电荷行为与光电催化活性之间的关系. 结果表明, 适量 In2O3敏化的 ZnO 光催化剂在可见光下 2 h 内对罗 丹明 B 的降解效率达到 95%, 是单纯 ZnO 纳米棒阵列的 2.4 倍.