An investigation into the effects of a nano-thick gold interlayer on polypyrrole coatings on 316L stainless steel for the bipolar plates of PEM fuel cells
An investigation into the effects of a nano-thick gold interlayer on polypyrrole coatings on 316L stainless steel for the bipolar plates of PEM fuel cells
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DOI：
10.1016/j.jpowsour.2007.09.089
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发表时间：
2008-01
影响因子：
9.2
通讯作者：
Yan Wang;D. Northwood
中科院分区：
文献类型：
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作者：
Yan Wang;D. Northwood
聚吡咯是最重要的导电聚合物之一，因其易氧化、易溶于水、可商业化而成为最重要的导电聚合物之一。此外，聚吡咯涂层在电池、燃料电池、电化学传感器、防腐涂层和药物输送系统中也有潜在的应用。在本研究中，首先在SS316L表面涂覆了一层很薄的金层，然后在上面铺设了一层聚吡咯涂层。用电化学成核和生长技术研究了聚吡咯在镀金SS316L表面的成核和生长机理。用扫描电子显微镜对聚吡咯涂层的形貌进行了表征。通过动电位测试确定了聚吡咯涂层的腐蚀参数。在模拟质子交换膜燃料电池的阳极和阴极环境中，对涂覆的SS316L进行了恒电位测试。模拟阳极环境的电位约为−0.1V，模拟阴极环境的电位约为0.6V，而模拟阴极环境的电位约为0.1V。与基材SS316L相比，镀金和聚吡咯后，SS316L的极化电阻提高了约6倍，腐蚀电流密度降低约7倍。计算还表明，聚吡咯/Au/SS316L燃料电池运行5000小时后，溶液中金属离子浓度已达到10ppm的目标。
Polypyrrole is one of the most important conductive polymers because it is easily oxidized, water soluble and commercially available. Also, polypyrrole coatings have potential applications in batteries, fuel cells, electrochemical sensors, anti-corrosion coatings and drug delivery systems. In this study, a very thin gold layer was first coated on SS316L, and then a polypyrrole coating was laid on top. The nucleation and growth mechanisms of polypyrrole on the gold-coated SS316L were studied by electrochemical nucleation and growth techniques. SEM was used to characterize the polypyrrole coating morphology. Potentiodynamic tests were performed to determine the corrosion parameters of the polypyrrole coatings. Potentiostatic tests of the coated SS316L were conducted in simulated anode and cathode environments of a PEM fuel cell. The simulated anode environment was at a potential of about −0.1V versus SCE purged with H2and the simulated cathode environment was at a potential of about 0.6V versus SCE purged with O2. After coating with Au and polypyrrole, the polarization resistance of SS316L is increased about six times, and the corrosion current density is decreased about seven times, compared to the base SS316L. Also, our calculations show that the metal ion concentration in solution for the polypyrrole/Au/SS316L had met the target of 10ppm after 5000h fuel cell operation.