手性聚苯胺纳米纤维的电化学制备

摘要

Chiral polyaniline ( PANI) nanofibers were synthesized via facilely potentiostatic electropolymeriza-tion method without template in the presence of ( IS) -( +) -camphor-10-sulfonic acid(D-CSA) or ( IR) -( -)-camphor-10-sulfonic acid(L-CSA) as the dopant. The morphology and optical property of chiral PANI nanofibers were characterized with scanning electron microscopy ( SEM ) , transmission electron microscopy ( TEM ) , UV-Vis spectrum(UV-Vis) and circular dichroism(CD) . Combined with the average diameter of micelles and zeta-potential of different deposition solutions, the formation mechanism and the enhanced optical activity of the optical PANI nanofibers were studied. The morphology of PANI nanofibers without the helical structure was consistent with the change of the concentration of aniline in the deposition solution when the concerntion of CSA was 1 mol/L. Furthermore, the chiral PANI nanofibers induced by different chiral CSA exhibited mirror-imaged circular dichroism spectra with high ellipticity, indicating the stereochemical selectivity of the molecular structure of PANI chain in the electrodeposited process. The colors and optical activities of the chiral PANI nanofibers not only can be kept with the chemical dedoping/redoping treatment, but also can reversibly varied with the different oxidized forms which were controlled via electrochemical route.%采用恒电位电聚合法制备了樟脑磺酸(CSA)掺杂的旋光异构性聚苯胺(PANI)纳米纤维.用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、紫外-可见吸收光谱(UV-Vis)和圆二色光谱(CD)对PANI纳米纤维的形貌和光学性质进行表征,结合电聚合溶液胶束平均粒径和ξ电位的测定,研究了具有旋光异构性PANI纳米纤维的形成机理和具有增强旋光异构性的原因.所制备的PANI纳米纤维具有无双螺旋结构,其形貌不随着苯胺浓度的改变而变化.不同手性樟脑磺酸掺杂制备的PANI纳米纤维具有镜像对称的旋光异构性,且具有较高的椭圆偏振率.这种手性PANI纳米纤维的颜色和旋光性均可通过化学掺杂/去掺杂或电化学掺杂改变氧化还原态而呈现可逆变化.