摘要
Direct methanol fuel cells have the advantages of simple system,convenient operation,high conversion rate and low carbon emission,which are considered as the environmental and friendly energy conversion devices.How-ever,the low activity,CO-tolerance and high cost of anode catalysts restrict the large-scale commercial appli-cations.Therefore,it is of great practical significance to design and construct the anodic catalysts with high activity,stability and low cost for methanol oxidation reaction.In this work,the PtM/Nb_(2)O_(5)-C(M=Co,Sn,Ni)catalysts are synthesized by the ethylene glycol solvothermal method using transition metal oxide Nb_(2)O_(5)as the support.The catalytic performance of different catalysts is further evaluated for alkaline MOR.The results show that the introduction of Ni(existing in Ni^(2+)and Ni^(3+))has the most obvious improvement for alkaline MOR performance.By adjusting the doped ratio of Pt:Ni,it is shown that PtNi/Nb_(2)O_(5)-C has the highest mass activity(3877.9 mA-mg_(pt)^(-1)),12 times that of the commercial Pt/C catalyst.CV,LSV,Tafel and EIS analyses show that PtNi/Nb_(2)O_(5)-C has the lowest onset potential and charge transfer resistance,and the fastest electrocatalytic oxidation rate of methanol.CA tests show that the electrochemical stability is also significantly improved with the introduction of Nb_(2)O_(5)and Ni.Combined with the structural characterization and electrochemical tests,it is found that the evident electronic effect among Pt and Ni,Nb_(2)O_(5)and the hydroxyl brought from Ni species are mainly ascribed for enhancing the activity,CO resistance and stability of PtNi/Nb_(2)O_(5)-C.
基金
National Natural Science Foundation of China(22075225,21706203,22038011 and 22005236)
Natural Science Basic Research Plan in Shaanxi Province of China(2022JZ-07)
State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology(MJNYSKL202308)
Key Research and Development Program in Shaanxi Province(2022QCY-LL-16).
