Mechanism Analysis and Application of Thermally Stimulated Currents in Hetero LB films

由两亲分子和长链脂肪酸交替形成的LB膜具有非中心对称的结构，其永久偶极子指向一个方向，适合于制作压电或热电元件。特别地，由热脉冲产生的受激电流可以用作红外传感器。使用苯基吡嗪衍生物和脂肪酸的杂LB膜的起源和结构的关系，这一电流进行了研究。当碳氢化合物链处于无序状态时，大的受激电流会改变其符号，一个实验接着一个实验。因此，为了将其用作传感器，我们必须使用电流的绝对值变化。另一方面，在相对低温下流动的热释电电流在-60 ° C左右始终为正，但在-20-0 ° C时变为负，具体取决于化合物。在吡嗪衍生物和水溶性阳离子聚合物之间的聚离子络合物的情况下，热释电系数没有增加，因为取向降低抵消了增加的自由度。

Hetero Langmuir-Blodgett (LB) films consisting of alternating monolayrs of amphiphile with large permanent dipoles and long-chain fatty acid take non-centrosymmetrical structure with dipoles oriented toward one direction, and they are amenable to be used for pyro- or piezo-electric elements. In particular, the stimulated current generated by the thermal impulse can be used as an infrared sensor. The origin and the structure-relationship of this current was investigated using hetero LB films of phenylpyrazine derivatives and fatty acids. The large stimulated currents that flows when the hydrocarbon chain is disordered changed its sign, experiment by experiment. Thus, for its utilization as a sensor, we have to use the absolute value change of the current. On the other hand, the pyroelectric current which flows at relatively low temperature, is always positive at around -60ﾟC, but it changed to negative at -20-0ﾟC depending on the compound. In the case of polyion complex between pyrazine derivative and water-soluble cationic polymer, the pyroelectric coefficient did not increased because of the cancellation of increased freedom by the orientation decrease.