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The support is prepared by carbonizing polyaniline-coated carbon black. On the one hand, it has the advantages of carbon black (excellent electrical conductivity, high specific surface area). On the other hand, the nitrogen−carbon shell has uniformly dispersed metal anchor sites, which effectively reduces the detachment of PtCo NPs from the carbon matrix and improves the activity and durability of the catalyst. Under acidic conditions, the mass activity (MA) of PtCo/C@NC-700 (0.53 A mg Pt −1 ) is 4.8 times that of JM Pt/C (0.11 A mg Pt −1

A strategy for preparing nitrogen-doped porous carbon (NPC-Co) using a dual-template method is reported in this study. The catalyst (PtCo/NPC-Co) with high catalytic performance for the oxygen reduction reaction (ORR) was developed after adding PtCo metal nanoparticles (NPs). Polydopamine can complex metals, encapsulate templates, and reduce metals. Therefore, polydopamine was selected as the carbon and nitrogen source. Then, ZnO and Co NPs were used as a double template to obtain a carrier (NPC-Co) with a high mesoporous ratio and high N content. The PtCo alloy NPs are homogeneously anchored on the support by highly dispersed N atoms originating from NPC-Co. PtCo/NPC-Co exhibited excellent catalytic performance and durability for oxygen reduction. The mass activity of PtCo/NPC-Co is 4.8 times that of commercial Pt/C catalysts. Furthermore, PtCo/NPC-Co showed excellent durability. The mass activity of PtCo/NPC-Co decreased by only 23% compared with that of Pt/C (49%) after 20,000 cycles. The interaction effect between NPC-Co and PtCo NPs enhanced the overall electrocatalytic performance. Additionally, the ORR mechanism is discussed in this study to advance our understanding of the electrocatalytic structure–activity relationship.

The research and synthesis of low-loading Pt-based catalysts with excellent catalytic performance and high stability are critical in achieving the commercial application of proton exchange membrane fuel cells. In this study, the Cu element is incorporated into a Co-based zeolitic imidazolate framework (ZIF) structure, and an N-doped low Pt-loading PtCuCo/NC alloy catalyst is synthesized using the impregnation reduction method with bimetallic CuCo-ZIF as a carrier. Incorporating a second metal Cu to Co-ZIF forms more metal-N bonds, increasing the N-doping content, and resulting in more structural defects. Meanwhile, the porous structure of ZIF can better disperse Pt/Pt alloy particles, which allows the generation and exposure of more oxygen reduction reaction active sites. PtCuCo/NC exhibits good catalytic activity (0.907 V) in electrochemical tests, with a high half-wave potential after 10,000 cycles and superior performance in single-cell tests. This study provides an idea for improving the performance of Pt-based fuel cell catalysts.

Alloy nanoframes have drawn wide attention in the field of electrocatalysis because of their high specific surface area, molecule accessible 3D pore structure, and excellent catalytic performance. However, due to abundant edges and corners, nanoframes are easy to collapse during the catalytic process, especially for oxygen reduction reaction. Herein, PtCu nanoframes are prepared through wet-chemical method and modified with Mo (Mo-PtCu NF) on the surface to improve the structural stability. Fully open nanoframe catalyst (A-Mo-PtCu NF/C) is finally obtained by selective etching excess Cu in Mo-PtCu NFs. Due to the synergistic effect of Cu and Mo, the electronic structure of Pt in A-Mo-PtCu NF/C is optimized to weaken the oxygen affinity. Meanwhile, the highly open structure of A-Mo-PtCu NF/C provides a large electrochemically active area. Therefore, the as-prepared nanoframe catalysts show enhancements in both mass activity and specific activity compared to the commercial Pt/C catalyst. Moreover, Mo-doping also stabilizes the structure and composition of the nanoframes, enhancing the stability for oxygen reduction reaction. Our research provides an effective strategy to improve the stability of highly active alloy nanoframes.