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炭载体的稳定性对于燃料电池电催化剂是至关重要的.本文中采用酚醛树脂作为前驱体,二氧化硅为模板剂,制备了多介孔且石墨化程度高的炭载体(HGMC).相比于商品Vulcan XC-72,HGMC具有中等的比表面积和高的石墨化程度,因此在电位循环扫描过程中具有较高的化学稳定性,然而HGMC碳层堆叠的结构不利于传质.为克服这一劣势,多壁碳纳米管(MWCNTs)作为隔离物加入至HGMC中以构建具有三维多尺度结构的载体(MSGC).与HGMC为载体担载Pt以及商品催化剂Pt/C-JM相比,由于炭载体的具有高稳定性以及三维多尺度结构,MSGC担载Pt后不仅使电催化剂的电化学稳定性提高,且氧还原反应过程中传质得到显著改善.
The stability of the carbon support is crucial for the fuel cell electrocatalyst.In this paper, a multi-mesoporous and graphitized carbon support (HGMC) was prepared by using phenolic resin as a precursor and silica as a template. Compared with the commercial Vulcan XC-72, HGMC possesses high specific surface area and high degree of graphitization, so it has higher chemical stability during potential cycle scanning, however, the structure of HGMC carbon layer stack is not conducive to mass transfer. In this disadvantage, multi-walled carbon nanotubes (MWCNTs) are added to the HGMC as a spacer to construct a three-dimensional multi-scale structure carrier (MSGC) .Compared with the HGMC as a carrier for Pt and the commercial catalyst Pt / Due to the high stability of the carbon support and the three-dimensional multi-scale structure, the electrochemical stability of the electrocatalyst is enhanced when the Pt is loaded on the MSGC, and the mass transfer is greatly improved during the oxygen reduction reaction.