Engineering platinum–nickel nano-alloys in hierarchically ordered porous cobalt-nitrogen-doped carbon for highly efficient electrocatalytic oxygen reduction

Abstract

PtNi alloy nanoparticles anchored on the hierarchically ordered macro-/mesoporous Co, N-doped carbon (PtNi/Co-N-OMMC) contribute to superior electrocatalytic performances for oxygen reduction under acidic condition. • Co-N-OMMC has ordered macro-/mesoporous structure and high specific surface area. • PtNi alloy particles are uniformly dispersed on Co-N-OMMC. • The synergistic effect between Co-N-OMMC and PtNi leads to good ORR activity. Herein, an ORR electrocatalyst with ultrafine PtNi alloy nanoparticles (sub-10 nm) anchored on the hierarchically ordered macro-/mesoporous Co, N-doped carbon (PtNi/Co-N-OMMC) is developed via an dual-template-assisted pyrolysis combined with one-step solvothermal method. As inspired, the PtNi/Co-N-OMMC catalyst shows superior ORR activity (half-wave potential (E 1/2 ) of 0.92 V) and high durability (negligible loss in E 1/2 over 2000 potential cycles) in acidic condition. The remarkable property of the PtNi/Co-N-OMMC catalyst for ORR benefits from the synergistic catalytic effect between PtNi nano-alloys and Co-N-OMMC for accelerating the reaction, the anchoring effect of the Co-N-OMMC support for suppressing nanoparticle migration and corrosion, the large surface area for highly dispersing PtNi nanoparticles and 3D interconnected ordered macro-/mesoporous structure for enhancing mass/charge transport throughout the electrode.