Enzymatically synthesized conducting polyaniline
Enzymatically synthesized conducting polyaniline
复制标题
DOI：
10.1021/ja982270b
复制
发表时间：
1999-01-13
影响因子：
15
通讯作者：
Samuelson, L
中科院分区：
文献类型：
--
作者：
Liu, W;Kumar, J;Samuelson, L
提出了一种新的酶促合成水溶性导电聚苯胺(PANI)/磺化聚苯乙烯（SPS）配合物的方法。辣根过氧化物酶（HRP）用于在聚阴离子模板磺化聚苯乙烯存在下聚合苯胺。合成简单，条件温和，可以在4.3 pH的缓冲水溶液中进行聚合，化学计量量的过氧化氢和催化量的酶。紫外可见吸收、FTIR、GPC、元素分析和电导率测量都证实了聚苯胺的电活性形式，与传统的化学合成形式相似，形成并与SPS络合。聚苯胺的可逆氧化还原活性随pH值的变化呈现出独特的滞后环。循环伏安法研究表明，在-0.2 ~ 1.2V的电位范围内，只有一组氧化还原峰，这表明PANI/SPS复合物的氧化稳定性更高。发现配合物的电导率随聚苯胺与SPS的摩尔比而增加。用纯配合物获得的电导率为0.005 S/cm，通过暴露于HCl蒸气进一步掺杂后，电导率可增加到0.15 S/cm。这种酶的方法提供了无与伦比的易于合成，可加工性，稳定性（电和化学）和环境相容性。
A novel strategy for the enzymatic synthesis of a water-soluble, conducting polyaniline (PANI)/sulfonated polystyrene (SPS) complex is presented. The enzyme horseradish peroxidase (HRP) is used to polymerize aniline in the presence of a polyanionic template, sulfonated polystyrene. The synthesis is simple, and the conditions are mild in that the polymerization may be carried out in a 4.3 pH buffered aqueous solution, with a stoichiometric amount of hydrogen peroxide and a catalytic amount of enzyme. UV-visible absorption, FTIR, GPC, elemental analysis, and conductivity measurements all confirm that the electroactive form of PANI, similar to that which is traditionally chemically synthesized, is formed and complexed to the SPS. The reversible redox activity of the polyaniline displays a unique hysteresis loop with pH change. Cyclic voltammetry studies show only one set of redox peaks over the potential range of -0.2 to 1.2V, which suggests that the PANI/SPS complex is oxidatively more stable. The conductivity of the complex is found to increase with the molar ratio of PANI to SPS. Conductivities of 0.005 S/cm are obtained with the pure complex and may be increased to 0.15 S/cm after additional doping by exposure to HCl vapor. This enzymatic approach offers unsurpassed ease of synthesis, processability, stability (electrical and chemical), and environmental compatibility.