Herein, for the first time, bimetallic nanoparticles supported on graphene nanoplatelets (PtNi/GNPs, PtFe/GNPs, PtCu/GNPs) were prepared as sequentially through supercritical carbon dioxide (scCO₂) technique. The physicochemical properties of the prepared catalysts were characterized by XRD, TEM, EDX, TGA, ICP-MS and Raman spectroscopy. Furthermore, the catalytic activity of bimetallic catalysts was tested using a three-cell cyclic voltammetry. PtNi/GNPs catalyst showed the best catalytic activity towards both hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR). Finally, to investigate the improvement of the cell performances, polarization curves were presented. It was found that the PtNi/GNPs catalyst exhibited highest performance (907.5 mA/cm ², 0.54 mW/cm ² @ 0.6 V) when the catalyst was used as anode electrode. We believe that this work will serve as a guide to the fuel cell research community in the selection of a promising route for the development of new low-cost and efficient electrocatalysts for PEMFC.

本文中，首次通过超临界二氧化碳（scCO ₂）技术依次制备了负载在石墨烯纳米片上的双金属纳米颗粒（PtNi / GNPs，PtFe / GNPs，PtCu / GNPs）。通过XRD，TEM，EDX，TGA，ICP-MS和拉曼光谱对制备的催化剂的理化性质进行了表征。此外，使用三单元循环伏安法测试了双金属催化剂的催化活性。PtNi / GNPs催化剂对氢氧化反应（HOR）和氧还原反应（ORR）均显示出最佳的催化活性。最后，为了研究电池性能的改善，给出了极化曲线。据发现，所述PtNi /的GNP催化剂具有最高性能（907.5毫安/厘米²，0.54毫瓦/平方厘米² @ 0.6V）时的催化剂被用作阳极电极。我们认为，这项工作将为燃料电池研究界提供指导，为开发新型低成本高效PEMFC电催化剂的有前途的路线选择。