Electrode effect on photohole generation in smectic phenylnaphthalene liquid crystalline photoconductor
Electrode effect on photohole generation in smectic phenylnaphthalene liquid crystalline photoconductor
复制标题
电极效应对近晶苯基萘液晶光电导体光空穴产生的影响
DOI：
10.1063/1.373652
复制
发表时间：
2000
影响因子：
3.2
通讯作者：
J. Hanna
中科院分区：
文献类型：
--
作者：
Hong Zhang;J. Hanna
通过稳态和瞬态光电流测量，研究了2-（4′-辛基苯基）-6-十二氧基萘（8-PNP-O12）液晶光导体在不同光照接触电极条件下的近晶相光孔生成过程。结果表明，根据电极材料的不同，空穴的光产生有两种不同的过程：分别采用Al、Pt或In2O3-SnO2电极时，本体中Onsager型光载流子的产生和延迟μs的电极增强空穴光注入。后者的产率比本体产率高一个数量级，但随着分子有序度从近晶B相到近晶A相再到各向同性相的退化而降低。根据光谱响应和电子受体化学掺杂效应的附加实验结果，得出了光空穴注入的结论。
The photohole generation process in the smectic phases of a liquid crystalline photoconductor, 2-(4′-octylpheny)-6-dodecyoxylnaphthalene (8-PNP-O12) with different illuminated contact electrodes was investigated through steady-state and transient photocurrent measurements. It was revealed that the photogeneration of holes was governed by two different processes according to the electrode materials: the Onsager type of photocarrier generation in the bulk and the electrode-enhanced hole photoinjection with a delay of μs when Al, and either Pt or In2O3–SnO2 electrodes are applied, respectively. In the latter process, the photogeneration yield was one order of magnitude larger than that in the bulk generation process, but decreased as the molecular ordering degraded from the smectic B phase to the smectic A phase, then to the isotropic phase. According to the spectral response and the results of additional experiments on the effect of chemical doping with electron acceptors, the photohole injection was conclu...