Abstract
Proton exchange membrane water electrolysis(PEMWE)technology is regarded as a significant development direction for future green hydrogen production technology,which has advantages in rapid response,high hydrogen purity,high current density,and high compatibility with renewable energy sources,etc.As crucial components of PEM hydrogen production stacks,metal bipolar plates suffer from oxidation and corrosion during stack operation,which results in increased interface contact resistance(RIC),shortened stack's service life and reduced water electrolysis efficiency.At present,the lack of high-performance bipolar plates has become one of the key factors limiting the commercial application of PEM hydrogen production technology.As a result,developing low-cost,corrosion-resistant,and highly conductive protective coatings of bipolar plates has been a hot research topic in PEM hydrogen production technology.
In this context,this paper outlines the basic principles and present situation of hydrogen production by water electrolysis technology.It introduces the main types,characteristics,and issues of PEM water electrolyzer bipolar plate materials.More importantly,this paper provides a comprehensive overview of the current research on protective coatings for bipolar plates used in PEM water electrolyzers,including their preparation methods,structural characteristics,anti-corrosion properties in simulated water electrolysis conditions,contact resistance,and experimental validation under PEM water electrolysis conditions.The types of coating materials are mainly metals,metal nitrides,conductive oxides,metal phosphides,and carbides.It indicates that a thin noble metal Pt coating offers an effective solution for the electrical conductivity and corrosion protection of titanium bipolar plates,yet it fails to protect stainless steel bipolar plates against corrosion.Highly corrosion-resistant metal coatings(Nb,Ti,etc.)with high thickness provide a feasible technical path for low-cost bipolar plates made of stainless steel or copper.Metal nitride coatings exhibit excellent electrical conductivity and thermal stability,but their corrosion resistance is inadequate in aggressive corrosive environments.Further improvement in the electrochemical stability of nitride coating is still needed to target electrolytic cell applications.Multiphase composite design may provide a promising technical path for this purpose.From a low-cost perspective,some conductive and corrosion-resistant materials(e.g.Ti4O7)provide new and possible solutions for protection of bipolar plates,which exhibit the similar water electrolysis performance to Pt coatings when applied to the surface of bipolar plates.However,a long-term verification test is currently lacking in the present study.The amorphous carbon-based coatings also attract strong interests in PEM water electrolyzers because of their low cost and high electrical conductivity.Notably,it just tends to be used for the cathode-side protection of bipolar plates due to intolerance to high potential.In addition,this review synthesizes critical performance data,specifically corrosion resistance and contact resistance,for representative coatings when tested under simulated PEM water electrolysis conditions.A comparative assessment of these coatings is conducted across parameters such as fabrication complexity,post/after corrosion contact resistance stability,and high-potential durability.Finally,the study outlines future trends in coating development and preparation technologies,providing actionable insights for the design,development,and industrial deployment of advanced bipolar plate coatings in PEM water electrolysis systems.关键词
电解水制氢/质子交换膜/双极板/涂层/耐腐蚀性能/界面接触电阻Key words
electrolysis of water to produce hydrogen/proton exchange membrane/bipolar plates/coating/corrosion resistance/interface contact resistance分类
矿业与冶金
