反向胶束法制备聚3,4-乙烯二氧噻吩纳米粒子的光电性能和热稳定性

Photoelectric Properties and Thermal Stability of PEDOT Nanoparticles Based on Reversed Micelle Method

采用聚合和掺杂同时进行的反向胶束体系制备了粒径分散较小的聚3,4-乙烯二氧噻吩(PEDOT)纳米粒子,利用紫外-可见光光谱(UV-Vis)、X射线衍射(XRD)和扫描电子显微镜(SEM)等分析方法对纳米粒子进行了表征.实验结果发现,氧化剂用量、超声处理、聚合温度及掺杂程度对PEDOT纳米粒子的形貌、电性能及热稳定性有不同程度的影响.根据实验结果对反向胶束法制备PEDOT纳米粒子过程进行优化发现,在PEDOT纳米粒子聚合过程中,甲基苯磺酸有效掺杂浓度约为0.17mol/L时,PEDOT链的取向最规则,在6.7°,12.7°,25°出现衍射峰,掺杂剂的有效掺杂使得纳米粒子中分子链的取向不同,并可以获得较高的电导率(>100S/cm)的PEDOT纳米粒子,当粒子的尺寸小于20nm后电导率降低;热失重法(TG)分析结果表明,PEDOT纳米粒子的热稳定性比普通块材好,掺杂剂浓度对纳米粒子的热稳定性有一定影响.

In recent years,conducting polymer nanostructure has been attracted more attentions due to their excellent optic,electric and gas sensitivity performances.Based on a new type of conducting polymer poly（3,4-ethylenedioxythiophene）（PEDOT）,small-sized PEDOT nanoparticles were prepared by reversed micelle method and characterized by UV-Vis spectroscopy,scanning electron microscopy（SEM） and XRD.The optical and electrical properties and the thermal stability of PEDOT nanoparticles were investigated.The results show that the amount of oxidizer,ultrasonic treatment,polymerizing temperature and doping degree have different influence on morphology,electrical ability and gas sensitivity of PEDOT nanoparticles.The Bragg peaks of the nanoparticles at 6.7°,12.7°,25° were observed by XRD and this well orientation of molecular chain was due to the effective doping of p-toluenesulfonate,which also resulted in an enhancement of thermal stability of nanoparticles than conventional PEDOT.