摘要
利用电化学方法在自组装一层对氨基硫醇 (PATP)的金电极上制备三种氧化还原态的聚苯胺 (PANI)膜 . PANI膜底层比较致密 ,表面呈山包状 ,该膜在 K3Fe(CN) 6 /K4 Fe(CN) 6 溶液的循环伏安图表明了部分氧化态 PANI膜具有良好的电子传输性能 .从光电流谱得到氧化态 PANI的禁带能为 1 .45 e V.首次发现部分氧化态 PANI膜的光电流谱遵循 Fowler定律 (IPCE1 / 2 ～ hν呈线性 ) ,具有内光电发射的性质 .通过 Fowler图得出部分氧化态 PANI的绝缘母体的禁带宽度为 3 .3 3 e V,并且证实该绝缘母体为还原态 PANI.从 Mott-Schottky图得到部分氧化态和还原态 PANI的平带电位都为 0 .63 V(vs. SCE) .提出了和 PANI的颗粒金属岛导电模型一致的内光电发射机理来解释部分氧化态
After self\|assembling a \%p\%\|aminothiophenol(PATP) monolayer on bare Au electrode, polyaniline(PANI) films were prepared by electropolymerization on the modified Au electrode and three forms of PANI(reduced PANI, partially\|oxidized PANI and oxidized PANI) were obtained by electrochemical method. The SEM pattern shows that there are some hills of PANI on a compact layer of PANI. The cyclic votammograms of the probe\[K\-3Fe(CN)\-6/K\-4Fe(CN)\-6\] for the three forms of PANI film show that partially\|oxidized PANI has a good electron transport performance. The potential dependence of magnitude and spectra of the photocurrent of PANI films were observed. The bandgap energy of 1.45 eV for oxidized PANI, which is the threshold energy of its photocurrent spectra, was obtained. The spectra of photocurrent for partially\|oxidized PANI film shows that it has the characteristics of sub\|band gap photocurrent spectra and follows Fowler rule(IPCE\+\{1/2\}～\%hν\%). The bandgap energy of insulating matrix in partially\|oxidized PANI is determined as 3.33 eV by the Flowler plots, and the insulating matrix in partially\|oxidized PANI is verified to be reduced PANI. The flat\|band potential, in the order of 0.63 V \%vs\%. SCE, is obtained from Mott\|Schottky plots. A photoelectrochemical process based on internal photoemission in partially\|oxidized PANI, which agrees with the model of granular metal island that assumes metallic polymer particles are embedded in the insulating matrix, is proposed.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第3期432-436,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金 (批准号 :2 983 3 0 60
2 0 173 0 44
2 0 0 2 3 0 0 1)
教育部科技研究项目 (批准号 :99177)资助
