ORR properties of S-modified Co 3 O 4 @S-g-C 3 N 4 /C catalyst in alkaline electrolyte

Developing high-efficiency and low-cost electrocatalysts for oxygen reduction reaction (ORR) is one of the key objectives for fuel cells. In this work, S-modified Co3O4@S-g-C3N4/C catalyst was prepared by combining pyrolysis with ultrasonic method. Transmission electron microscopy analysis indicated that the obtained catalyst had a core-shell structure, which used Co3O4 as its core and 1.5-nm-thick S-interspersed g-C3N4 encapsulated Co3O4 as shell. When the ratio of S to g-C3N4 was 1:3, the as-prepared catalyst Co3O4@ S-g-C3N4/C exhibited positive onset potential and higher limiting diffusion current density of 4.00 mA cm–2 @0.8V, which was 10 and 37% higher than that of Co3O4@g-C3N4/C and Co3O4/C, respectively. After 2000 CV cycles, the catalyst also showed good durability.