铝合金表面石墨烯-二氧化锡超疏水膜的构建及缓蚀协同机制

Bipolar plate is one of the key materials to determine the wide application of proton exchange membrane fuel cell (PEMFC). Due to the low density, high intensity and high conductivity, aluminum alloys can be regarded as promising materials applied to ideal potential materials candidates for bipolar plate. However, surface contact resistance increasement caused by the corrosion of aluminum alloys seriously restricts its application for PEMFC in essence. To alleviate corrosion effect of aluminum alloys for bipolar plate, here graphene-tin dioxide superhydrophobic film coating strategy is proposed to improve the anti-corrosion and conductivity, because of the unique two-dimensional structure and excellent electron mobility from graphene and high stability from tin dioxide. This research will focus on the control of micro-nano structure and component of graphene-tin dioxide film, as well as their effects on superhydrophobicity, anti-corrosion capacity, and conductivity of aluminum alloys. The synergistic mechanism of anti-corrosion ability and electron transfer associated with graphene-tin dioxide film will be emphasized. The characterization technique of surface morphology and in-situ electrochemical method are used to investigate the mechanism of electron transfer, corrosion inhibition and film-passivation of aluminum alloy for simulating PEMFC conditions and illustrate its corrosion kinetics. The proposal will provide theoretical and experimental instruction for the promotion of inhibition and conductivity of aluminum alloy for PEMFC.

双极板是影响质子交换膜燃料电池广泛应用的关键材料之一。铝合金材料密度小、强度高、导电性好，是一种潜在的理想双极板材料，但其在电池工况条件下易发生腐蚀并导致表面接触电阻增加，严重制约了它的应用。为此，本项目提出利用石墨烯独特的层状结构和优异的电子迁移性及二氧化锡的化学稳定性，在具有微纳结构的铝合金表面上构建石墨烯-二氧化锡超疏水复合膜，以提升铝合金双极板的耐蚀性能与导电性能。研究铝合金表面微纳结构、石墨烯和二氧化锡的组成和结构调控，对铝合金材料的超疏水性、耐蚀性和导电性的相互影响规律；着重探索石墨烯和二氧化锡之间的相互作用增强耐蚀性能和电子迁移性能的协同机制。结合表面形态表征技术和原位电化学测试方法研究上述铝合金在模拟电池工作环境中的金属离子溶解、迁移行为、表面膜钝化机制和腐蚀机制，深入阐明其腐蚀动力学过程。研究结果将为提高铝合金双极板的耐蚀性能和导电性能提供理论基础和实践指导。

铝合金材料由于其密度小、强度高、导电性好在质子交换膜燃料电池双极板中被广泛应用。然而其在电池工况条件下易发生腐蚀并导致表面接触电阻增加，严重制约了它的应用。本项目利用石墨烯独特的层状结构和优的电子迁移性及二氧化锡的化学稳定性，在具有微纳结构的铝合金表面上构建石墨烯-二氧化锡超疏水复合膜，以提升铝合金双极板的耐蚀性能与导电性能项目。. 项目首先借助化学刻蚀和电化学氧化法方法在铝合金表面构建合适的微纳结构，继而通过涂覆法、自组装和水热法以及电化学沉积法在铝合金表面构筑石墨烯-二氧化锡复合膜，系统研究了铝合金表面微纳结构以及石墨烯、二氧化锡的形貌和结构对可控构建具有高耐蚀性、高导电性、超疏水的石墨烯-二氧化锡复合膜的影响规律。揭示石墨烯和二氧化锡之间的相互作用对提升铝合金的耐蚀性能和电子迁移性能的协同机制。研究铝合金双极板在模拟PEMFC 环境中的金属离子溶解、迁移行为、表面膜钝化机制和腐蚀机制，阐明了其腐蚀动力学过程。基于本项目工作为提升PEMFC用铝合金双极板的耐蚀性能与导电性能提供理论基础和实践指导，围绕本项目研究成果，在《corrosion science》等期刊发表标注本项目资助的论文8篇，其中1篇入选ESI 高被引论文,申请国家发明专利12项，授权6项，培养硕士研究生5名, 举办第十九次全国电化学大会， 项目组主要成员参加学术交流9人次。