Effect of Manganese oxide with its discrete valences on Fe 2 O 3 /C to form (MnO x -Fe 2 O 3 /C) hybrid nanocomposite electrodes for enhanced ORR activity
Discuss this preprint
Start a discussion What are Sciety discussions?Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
Electrocatalysts play a vital role in recently emerged energy conversion devices. The present study has been undertaken to synthesize non-precious metal oxides, i.e., manganese oxide-iron oxide/carbon (MnO x -Fe 2 O 3 /C) hybrid composites, as high-performance electrocatalysts for the oxygen reduction reaction (ORR). The synthesis involved a simple and low-cost co-precipitation method, where MnO x (MnO 2 , Mn 2 O 3 , Mn 3 O 4 ) served as dopants to Fe 2 O 3 supported on carbon derived from chitosan. The biopolymer-derived carbon provided a highly conductive framework, facilitating uniform dispersion of metal oxides and enhancing electron transfer. The electrochemical investigations carried out via cyclic and linear scan voltammetry revealed that MnO 2 -Fe 2 O 3 /C exhibited superior ORR activity with higher current density, lower onset potential, and excellent methanol tolerance as compared to other composites tested. The synthesized MnO 2 -Fe 2 O 3 /C composite offered lower charge transfer resistance, faster kinetics, and elevated electrocatalytic efficiency when subjected to electrochemical impedance spectroscopy. The enhanced ORR performance of the MnO 2 -Fe 2 O 3 /C composite might be attributed to the synergistic interaction between MnO x and Fe 2 O 3 along with the conductive behavior of the chitosan-derived carbon matrix. These findings demonstrate that MnO 2 -Fe 2 O 3 /C is a promising non-precious metal electrocatalyst for ORR, offering a sustainable, low-cost alternative to noble metal catalysts for fuel cells.
