Developing a high-performance ORR (oxygen reduction reaction) catalyst at low cost has been a challenge for the commercialization of high-energy density and low production cost aluminium-air batteries. Herein, we report a catalyst, prepared by pyrolyzing the shell waste of peanut or pistachio, followed by concurrent nitrogen-doping and FeCo alloy nanoparticle loading. Large surface area (1246.4 m2 g-1) of pistachio shell-derived carbon can be obtained by combining physical and chemical treatments of the biomass. Such a large surface area carbon eases nitrogen doping and provides more nucleation sites for FeCo alloy growth, furnishing the resultant catalyst (FeCo/N-C-Pistachio) with higher content of N, Fe, and Co with a larger electrochemically active surface area as compared to its peanut shell counterpart (FeCo/N-C-Peanut). The FeCo/N-C-Pistachio displays a promising onset potential of 0.93 V vs. RHE and a high saturating current density of 4.49 mA cm-2, suggesting its high ORR activity. An aluminium-air battery, with FeCo/N-C-Pistachio catalyst on the cathode and coupled with a commercial aluminium 1100 anode, delivers a power density of 99.7 mW cm-2 and a stable discharge voltage at 1.37 V over 5 h of operation. This high-performance, low-cost, and environmentally sustainable electrocatalyst shows potential for large-scale adoption of aluminium-air batteries.
Zinc–air batteries with seawater
electrolyte utilize abundant
and cheap resources. However, it requires an electrocatalyst with
high bifunctional activity in seawater. In this work, a carbon electrocatalyst
is obtained via one-step pyrolysis of the shell waste of cranberry
beans. During the oxygen reduction reaction (ORR) in seawater electrolyte,
the cranberry bean shell-derived carbon catalyst exhibits an ORR onset
potential of 0.69 V vs RHE and an ORR saturating current density of
2.93 mA cm–2, which are promising compared to the
ORR performance of Pt/C in seawater electrolyte (0.78 V vs RHE and
3.15 mA cm–2). During OER (oxygen evolution reaction)
in seawater electrolyte, the carbon catalyst shows an overpotential
of 582 mV at 5 mA cm–2, 35 mV smaller than the commercial
Ir/C catalyst (617 mV). Furthermore, when the catalyst is applied
to the zinc–air battery with seawater electrolyte, the cell
is able to exhibit discharge and charge voltages of 0.93 and 2.2 V,
respectively, which are stable for more than 120 cycles of the cycling
test. This work highlights the fabrication of metal–air batteries
with cost-effective and sustainable resources.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.