posted on 2023-11-21, 11:03authored byKoorosh
Firouz Tadavani, Mohammad Zhiani, Hussein Gharibi, Haideh Balali Dehkordi
Metal–air batteries can be developed on a large
scale using
suitable nonprecious metal catalysts to replace Pt/C in the cathode
electrode. The production of an iron-based N-doped carbon electrocatalyst
(Fe–NC) from a metal–organic framework precursor through
the pyrolysis process was successfully achieved in this work. Brunauer–Emmett–Teller
analysis of the Fe–NC electrocatalyst showed a large surface
area (621 m2 g–1). X-ray photoelectron
spectroscopy and Raman results confirmed the existence and variety
of nitrogen species in the structure of the electrocatalyst as defect
agents, and active sites induced astounding oxygen reduction reactions
as efficient cathodes for zinc–air batteries. The electrochemical
test in the 0.1 M KOH solution displayed that the oxygen reduction
cathodic peak appeared at 0.897 VRHE.
The linear sweep voltammetry revealed excellent onset potential (Eonset = 1.02 VRHE), half-wave potential (E1/2 = 0.892 VRHE), and limiting current density (4.87 mA
cm–2). The durability test of the Fe-NC electrocatalyst
indicated only a 22 mV negative shift in the E1/2 after 10,000 continuous potential cycles. The open circuit
voltage and specific capacity of Fe–NC were 1.47 V and 749
mA h g–1 in a Zn–air battery system, respectively.
Due to the acceptable oxygen reduction activity of the synthesized
electrocatalyst, the Fe–NC electrocatalyst can be used in a
wide range of energy applications.