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  • Exploring Enhanced Oxygen Reduction Reactions: A Study on Nanocellulose, Dopamine, and Cobalt Complex-Derived Non-Precious Electrocatalyst
Title: Exploring Enhanced Oxygen Reduction Reactions: A Study on Nanocellulose, Dopamine, and Cobalt Complex-Derived Non-Precious Electrocatalyst
Cobalt-based catalysts are recognized as promising electrocatalysts for oxygen reduction reactions (ORRs) in fuel cells that operate within acidic electrolytes. A synthesis process involving a cobalt complex, nanocellulose, and dopamine, followed by pyrolysis at 500 °C under a nitrogen atmosphere, was used to create a cobalt and nitrogen-doped carbonaceous material. Additionally, urea was incorporated to enhance nitrogen doping in the carbonaceous material. The morphology and structure of the material were examined using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD), where SEM unveiled dispersed metal oxides within the carbonaceous framework. Energy Dispersive X-ray Spectroscopy (EDS) analysis showed an even distribution of elements across the cobalt-doped carbonaceous material. X-ray Photoelectron Spectroscopy (XPS) analysis further highlighted significant alterations in the elemental composition due to pyrolysis. The electrochemical behavior of the cobalt-doped carbonaceous material, with respect to the oxygen reduction reaction (ORR) in an acidic medium, was investigated via cyclic voltammetry (CV), revealing an ORR peak at 0.30 V against a reversible hydrogen reference electrode, accompanied by a notably high current density. The catalyst’s performance was evaluated across different pH levels and with various layers deposited, showing enhanced effectiveness in acidic conditions and a more pronounced reduction peak with uniformly applied electrode layers. Rotating disk electrode (RDE) studies corroborated the mechanism of a four-electron reduction of oxygen to water, emphasizing the catalyst’s efficiency.  more » « less
Award ID(s):
2223984
PAR ID:
10621620
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
MDPI (Multidisciplinary Digital Publishing Institute)
Date Published:
Journal Name:
Catalysts
Volume:
14
Issue:
9
ISSN:
2073-4344
Page Range / eLocation ID:
613
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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