过氧化氢在磺酸二茂铁掺杂的聚苯胺上的电催化氧化

在含有磺酸二茂铁溶液中合成的聚苯胺（PAnFc）和不含磺酸二茂铁溶液中合成的聚苯胺（PAn）,在pH 5.0的缓冲溶液中均能催化过氧化氢的氧化,但PAnFc的催化活性高于PAn.催化效应的证据是过氧化氢在裸铂电极上的氧化电位为0.59 V(vs SCE),而在PAnFc电极仅是0.48 V,以及过氧化氢在PAnFc电极上的阳极峰电流是裸铂电极上的5.3倍.根据这种催化特性,用PAn和PAnFc固定葡萄糖氧化酶形成酶电极.实验结果表明,PAnFc酶电极的响应电流比PAn酶电极高得多,而且响应快.这是由于PAnFc在pH 5.0缓冲液中的电化学活性高于PAn,以及掺杂在聚苯胺中的磺酸二茂铁起着重要的电荷传递作用.

The Electrocatalytic Oxidation of Hydrogen Peroxide on Polyaniline Doped with Ferrocenesulfonic Acid

Polyaniline(PAnFc) synthesized in a presence of ferrocenesulfonic acid and polyaniline(PAn) synthesized in the absence of ferrocenesulfonic acid can catalyze the electrochemical oxidation of hydrogen peroxide in a buffer solution with pH 5.0,but the catalytic activity of PAnFc is higher than that of PAn.Evidence for this catalytic effect is that the oxidation potential of hydrogen peroxide shifts from 0.59 V on the bare platinum electrode to 0.48 V (vs SCE) on the PAnFc electrode,and the anodic peak current of hydrogen peroxide on the PAnFc electrode is 5.3 times as high as that on the bare platinum electrode.Based on this catalytic property,both PAn and PAnFc were used for immobilization of glucose oxidase to fabricate the enzyme electrodes.The experimental results indicate that the response current of the PAnFc enzyme electrode is much higher than that of the PAn enzyme electrode,the response time of PAnFc enzyme electrode is shorter than that of the PAn enzyme electrode.This is due to the fact that the electrochemical activity of PAnFc is higher than that of PAn in the buffer solution with pH 5.0 and ferrocenesulfonic acid doped into polyaniline plays an important role in the charge transfer.