Elongated Fe–N–C containing trace atomic Co dopants for high power density PEMFCs  

作　　者：Jiayao Cui Junyong Min Hao Wang Jianglan Shui Lishan Peng Zhenye Kang Jieyuan Liu Qingjun Chen Shuo Bai Yanrong Liu 

机构地区：[1]CAS Key Laboratory of Green Process and Engineering,State Key Laboratory of Mesoscience and Engineering,Beijing Key Laboratory of Ionic Liquids Clean Process,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China [2]School of Chemical Engineering,University of Chinese Academy of Sciences,Beijing 100049,China [3]Longzihu New Energy Laboratory,Zhengzhou Institute of Emerging Industrial Technology,Henan University,Zhengzhou 450000,China [4]School of Materials Science and Engineering,Beihang University,Beijing,China [5]Ganjiang Innovation Academy Chinese Academy of Sciences,Ganzhou 341000,China [6]State Key Laboratory of Marine Resource Utilization in South China Sea,Hainan Provincial Key Lab of Fine Chemistry,School of Chemical Engineering and Technology,Hainan University,Haikou 570228,China

出　　处：《Industrial Chemistry & Materials》2024年第4期634-643,共10页工业化学与材料（英文）

基　　金：This work was supported by the Beijing Natural Science Foundation(No.2202052 and Z200012);National Natural Science Foundation of China(No.92061125);Hebei Natural Science Foundation(B2020103043);Science and Technology Program of Inner Mongolia(2021GG0237);Key R&D Program of Henan Province(No.231111241800).

摘　　要：Developing single-atom Fe–N_(4)/C catalysts is crucial for the large-scale implementation of proton exchange membrane fuel cells(PEMFCs).While Fe–N_(4)/C catalysts are inherently active in accelerating the slow ORR process,their performance is still inferior to that of Pt/C.Herein,a trace Co-doped Fe single-atom catalyst(Fe(tCo)–N–C)containing more active Fe_(2)N_(8) sites has been synthesized.Interestingly,compared with typical FeN4 sites in an Fe–N–C electrocatalyst,the Fe_(2)N_(8) sites generate a larger Fe–N bond length due to Co-doping.The elongated Fe–N bond in Fe_(2)N_(8) lowers the d-band center and charge density of iron sites,enhancing the ORR process by facilitating the formation of*OOH and generation and desorption of*OH.Fe(tCo)–N–C manifested excellent acidic and alkaline ORR activity,with a half-wave potential(E_(1/2))of 0.80 V in HClO_(4) solution and 0.89 V in KOH medium.More importantly,high peak power densities(Pmax)were realized by applying Fe(tCo)–N–C in PEMFCs,with the Pmax reaching 890 mW cm^(-2) in H_(2)–O_(2) and 380 mW cm^(-2) in H_(2)–air.Additionally,trace Co dopants in the catalyst improved carbon graphitization and provided high ORR catalytic stability.This research introduces an innovative approach to engineering highly active Fe_(2)N_(8) sites,providing valuable insights for the sustainable progress of PEMFC technology.

关 键 词：Proton exchange membrane fuel cells Oxygen reduction reaction Platinum-group-metal-free catalysts Single-atom catalysts Bimetallic active sites 

分 类 号：O64[理学—物理化学]