Scalable preparation of Pd/bacteria-rGO(CNT, Ketjen) composites for efficient oxygen reduction catalyst.

In this paper, Pd catalysts supported on novel composite carbon supports were synthesized by the carbonization and hydrogen reduction of Pd2+-doped bacteria containing Ketjen EC600JD, CNT and rGO, respectively. The analysis results show that the prepared catalysts exhibit excellent ORR electrocatalytic performance in acid medium. The best ORR electrocatalytic performance was obtained for Pd/carbonized-bacteria-rGO, which exbibits a mass activity at 0.345 A mg−1 that is 9.58 times higher than commercial Pd/C, and meanwhile displays a better stability than that of Pd/C. The enhanced performance can be attributed to nitrogen doping and flexible carbon-coating microstructure. Herein, we elaborate an efficient and ecofriendly method for the synthesis of electrocatalysts used for oxygen reduction reaction. • Preparation of Pd/bacteria-rGO(CNT, Ketjen) catalysts is facile and eco-friendly. • rGO(CNT, Ketjen) can enhance conductivity of carbonized-bacteria composite. • The flexible carbon-coating microstructure can improve Pd catalyst performance. • Pd/bacteria-rGO catalysts show outstanding performance than standard Pd/C. • Nitrogen and phosphorus doping can enhance the catalyst performance. [ABSTRACT FROM AUTHOR]