硫酸溶液中非铂金属上苯胺的电聚合行为

通过电化学方法对0.1 mol/L H2SO4 0.1 mol/L C6H5NH2溶液中苯胺在电工纯铁(DT3)和代号为40 Cr、紫铜和钢材420、304、321和316 L表面上的电聚合行为、上述材料在0.1 mol/L H2SO4溶液中的电化学行为进行了研究。结果表明,DT 3、40 Cr和紫铜三种材料上占主导地位的金属溶解反应抑制苯胺的氧化聚合,导致上述材料表面不能形成聚苯胺;在0.1 mol/L H2SO4溶液有很宽钝化电位区的420、304、321和316 L不锈钢都可在0.1 mol/L H2SO4 0.1 mol/L C6H5NH2溶液中进行苯胺的电化学聚合。不锈钢表面钝化膜影响苯胺聚合的起始电位。苯胺在420、304和316 L钢表面的起始氧化电位在1 100 mV左右,而由于321钢表面钝化膜中钛氧化物的存在,则使苯胺聚合的起始电位负移至700 mV。电位区间和扫描圈数相同时,基底材料不影响聚苯胺膜层的电导率,但降低阳极电位可显著提高聚合物电导率,为电化学合成导电聚合物、提高薄层金属双极板抗腐蚀性能奠定一定的基础。

Aniline electropolymerization behavior on non-platinum metals in sulfuric acid solution

The behaviors of aniline electropolymerization on DT 3, 40 Cr, copper, 420, 304, 321 and 316 L stainless steel had been studied in 0.1 mol/L H2SO4 0.1 mol/L C6H5NH2 solution using electrochemical measurements.The corrosion behaviors of those materials in 0.mol/L H2SO4 solution were also investigated by potentiodynamic method.The results indicated that polyaniline could not be obtained on the surfaces of DT 3, 40Cr and copper in 0.1 mol/L H2SO4 0.1 mol/L C6H5NH2 solution because metals dissolution inhibited the polymerization of aniline.Polyaniline coatings were electrosynthesised on 420, 304, 321 and 316 L stainless steel, which had wide passive potential region in 0.1 mol/L H2SO4 solution, using 0.1 mol/L H2SO4 as supporting electrolytes. Original polymerization potential of aniline had related with the passive film of stainless steel. The values of polymerization potential on 420, 304 and 316 L stainless steel are all 1 100 mV while the polymerization potential on 321 stainless steel shifts negative to 700 mV for existence of titanium oxide in the passive film of 321. Different materials did not affect the electrical conductivity of polyaniline when the potential range and the scan numbers were set as the fixed values. Electrical conductivity was improved when decreasing anodic potential in cyclic voltammograms.