Abstract
In electrochemical energy devices,the operating conditions always exert enormous influence on electro-catalysts'performances.Phosphoric acid(PA),acted as the proton carriers,can be adsorbed on Pt surface,block active sites and affect the electronic structure of Pt unfavorably,which severely restricts the per-formance of high-temperature proton exchange membrane fuel cells(HT-PEMFCs).Herein,simply basic organic compounds,such as dicyandiamide(DCD),melamine(Mel)and cyanuric acid(CA),are decorated on Pt surface(DCD-Pt/C,Mel-Pt/C and CA-Pt/C)to induce the adsorption transfer of proton carriers.The decoration can not only inject electrons to Pt and enhance oxygen reduction reaction(ORR)activity but also can induce PA to transfer from Pt surface to organic compounds,decontaminating active sites.In addition,the organic compounds with the larger conjugated system and the smaller electronegativity of ligating atoms would have a greater interaction with Pt,causing a larger decoration amount on Pt surface,which leads to more excellent ORR activity and resistance to PA blockage effect.Therefore,Mel-Pt/C shows a peak power density of 629mW/cm2,exceeding commercial Pt/C(437mW/cm2),DCD-Pt/C(539mW/cm2)and CA-Pt/C(511 mW/cm2)with the same loading.
维普
万方数据