Conversion of peanut biomass into electrocatalysts with vitamin B12 for oxygen reduction reaction in Zn-air battery

The conversion of biomass into functional carbon materials as electrocatalysts for oxygen reduction reaction (ORR) is a new bridge to use agricultural residues for renewable energy industries. Herein, hierarchical porous carbon material doped with nitrogen and cobalt (Co)-based nanoparticles (N/CoPSAC) has been prepared from biomass (i.e. peanut shells and vitamin B12). The resulting catalyst of N/CoPSAC demonstrates excellent electrocatalytic activities in alkaline media, such as more positive on-set potential and half-wave potential, 4-electron oxygen reduction (n = 3.81) and outstanding stability. The observed ORR activities of N/CoPSAC can be attributed to the synergistic effect of interconnected 3D porous structure and heteroatom doping. Furthermore, the performance evaluation of N/CoPSAC in a more practical setup of Zn-air batteries shows superior durability to that of the benchmark Pt-based electrocatalysts. Hence, the N/CoPSAC electrocatalyst derived from peanut biomass holds a good potential to be used as an alternative for commercial Pt/C in Zn-air batteries.