Highly graphitized Co–N–C assisted Pt nanoparticles for enhanced oxygen reduction stability in acidic media

Highly graphitic carbon-supported Pt particles (Pt/Co–N–C) was developed. • Regulating the electronic structure of Pt through the strong metal-support interaction. • Intrinsic activity was increased by optimizing O 2 adsorption and lowering energy barrier. • High mass activity and excellent stability of Pt/Co–N–C were achieved. Developing durable supported Pt-based materials is essential for advancing the oxygen reduction reaction in fuel cells, as harsh electrocatalytic conditions often trigger corrosion of carbon supports. The support materials’ physical and chemical properties play a crucial role in the overall performance of Pt-based catalysts. Herein, a highly stable electrocatalyst (Pt/Co–N–C) consisting of small Pt particles coupled tightly with highly graphitized Co–N–C substrate for efficient catalysis was proposed. Pt/Co–N–C exhibited a remarkable mass activity in acidic media, 6.4 times higher than that of commercial Pt/C. Notably, Pt/Co–N–C displayed exceptional stability, with only a 3 mV decrease in half-wave potential and retaining 95.8% mass activity even after 50,000 potential cycles during the accelerated durability tests. Experimental and theoretical analysis highlighted the enhanced support-catalyst and electronic effects between Pt and Co–N–C matrix, thereby enhancing the mass transfer and preventing the structural degradation of the electrocatalyst. This work underscored the possibility of simultaneously modifying Pt active sites and carbon support as effective electrode catalysts in fuel cells. Download: Download high-res image (307KB) Download: Download full-size image