摘要
氧还原反应是质子交换膜燃料电池阴极催化反应的关键步骤。氧还原活性趋势图(火山图)中,贵金属Pt超高的催化性能显而易见,因此目前氧还原性能最佳的商业化催化剂仍然是碳载铂(Pt/C)。另一方面,Pt昂贵的价格也促使国内外研究者尝试开发Pt合金催化剂、非Pt催化剂等新型催化剂。在开发低Pt催化剂过程中,通过添加过渡金属来改变d带中心是较普遍的解决方案。研究者发现PtNi/C催化剂的氧还原性能远超商业化Pt/C催化剂,但催化剂中的过渡金属Ni在酸性条件下易溶解,从而破坏反应环境,导致稳定性较差。当前针对该问题的研究主要聚焦于调节催化剂晶面、表面应变以及组成结构,通过改变这些因素试图提高催化剂的电化学活性和耐久性。其中,由Pt_(3)Ni(111)面封闭形成的八面体纳米颗粒已经被认为是很有前途的氧还原反应电催化剂,成为了PtNi双金属催化剂中的研究热点。此外,对合金表面进行其他金属/非金属元素修饰,改善催化剂载体性质,也可以实现催化剂氧还原性能的提高。本文综述了近些年用于氧还原反应的Pt-Ni基催化剂的研究现状,主要包括通过催化剂形貌调控来控制暴露晶面、对催化剂进行表面修饰,以及载体性能优化和选用新的载体等方面。
Oxygen reduction reaction(ORR)is the key step in the cathodic catalytic reaction of proton exchange membrane fuel cell(PEMFC).It hasbeen found from trends in oxygen reduction activity(volcano plot)that noble metal Pt has super-high catalytic performance;therefore,the most active commercial catalyst for ORR is still Pt/C so far.On the other hand,driven by the scarce resources and high price of Pt,continuous and numerous research efforts have also been made worldwide,aiming to develop Pt alloy catalysts and non-Pt catalysts.Adding a transition metal to change the d band is the common solution to develop low Pt catalyst.Researchers found that PtNi/C catalyst has an ORR activity far exceeding the commercial Pt/C catalyst.However,during operation the transition metal Ni atoms are prone to leach in the acidic condition,collapse the near-surface structure,lose the active facets,depress the ORR activity,and thus result in low stability for practical application.Currently the corresponding research is mainly focused on regulating catalyst crystal plane,surface strain and structure.By changing these factors,the electrochemical activity and durability of the catalyst can be improved.In particular,the octahedral shape has made the most remarkable progress on the surface of Pt_(3)Ni(111)alloy,and the nanometer PtNi alloy octahedron sealed by(111)surface has become a very promising ORR bimetallic electrocatalyst.And besides,changing the support and element modification could also improve the ORR catalytic performance.This review addresses the current development of Pt-Ni based catalysts for oxygen reduction reaction.The main aspects entailed include:adjusting the exposed facet by morphology control,elements doping and modification,optimizing the support or developing new supports.
作者
逄芳钊
姚陈思琦
李安金
赵盘巢
李继刚
易伟
何建云
蒋云波
陈义武
PANG Fangzhao;YAO Chensiqi;LI Anjin;ZHAO Panchao;LI Jigang;YI Wei;HE Jianyun;JIANG Yunbo;CHEN Yiwu(Kunming Institute of Precious Metals,Kunming 650106,China;College of Science,Northeastern University,Shenyang 110819,China;Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China;China National Nuclear Industry Corporation 404,Jiayuguan 735112,Gansu,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2023年第1期154-162,共9页
Materials Reports
基金
国家自然科学基金(51864022)
陕西省重点研发项目(2019GY-193)
昆明市高层次人才引进创新技术进步项目(13020163)。