Preparation of Asymmetric Single-Atom Electrocatalysts for High-Performance Oxygen Reduction Reaction

Qiyue Cui

2022

Abstract

Metal-organic frameworks (MOFs) have been regarded as a kind of supramolecular non-noble metal-organic hybrids via the strong coordination bonds, which have a highly tunable porous structures, high surface area, and fully exposed and uniformly dispersed metal centers, facilitating mass transport and highly-efficient electron transfer. In this study, we explore the synthesis strategy to prepare hierarchical single-atom electrocatalysts with porous and conductive carbon supports based on a serial of MOFs templates. The various MOF templates were prepared by roomtemperature self-assembly or hydrothermal processes. The as-synthesized MOFs were well-designed for the construction of hierarchical nanostructures. Subsequently, a facile and controlled high-temperature pyrolysis treatment was applied for the as-synthesized MOF templates, which allowed the organic ligands to reduce metal centers by releasing hydrogen by changing themselves to porous and conductive carbon materials. Finally, the nanostructured morphology and electrical activity of the as-synthesized single-atom catalysts were investigated by the X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectrum, Spherical aberration electron microscopy, and synchrotron radiation characterization, electrochemical impedance, and cyclic voltammetry. Density Functional Theory (DFT) calculations suggest that the designed asymmetric planar four-ligand structure may be the most favorable catalytic sites. Previous studies were restricted by using Cu elements as the metal active centers and S1N3 as the ligands, but broadening the catalyst selection areas, e.g., using monoatomic metal centers such as Fe, Mn, and introducing P element in the ligand, may improve the electronic structure properties of the catalyst, which can effectively reduce the energy barrier in the ORR, a key rate-limiting step in fuel cells. Based on this idea, we investigated six asymmetric monoatomic electrocatalysts, namely, Fe-S1N3, Cu-S1N3, Mn-S1N3, Cu-P1N3, Fe-P1N3, and Mn-P1N3, respectively. The synthesized catalysts have abundant and fully exposed active sites, which can be applied in the cathode reaction of fuel cells and help human species to cope with the global energy crisis and the energy transition in fields such as electric vehicles.

Paper Citation

in Harvard Style

Cui Q. (2022). Preparation of Asymmetric Single-Atom Electrocatalysts for High-Performance Oxygen Reduction Reaction. In Proceedings of the 1st International Conference on Food Science and Biotechnology - Volume 1: FSB; ISBN 978-989-758-638-5, SciTePress, pages 100-105. DOI: 10.5220/0012003100003625

in Bibtex Style

@conference{fsb22,
author={Qiyue Cui},
title={Preparation of Asymmetric Single-Atom Electrocatalysts for High-Performance Oxygen Reduction Reaction},
booktitle={Proceedings of the 1st International Conference on Food Science and Biotechnology - Volume 1: FSB},
year={2022},
pages={100-105},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0012003100003625},
isbn={978-989-758-638-5},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 1st International Conference on Food Science and Biotechnology - Volume 1: FSB
TI - Preparation of Asymmetric Single-Atom Electrocatalysts for High-Performance Oxygen Reduction Reaction
SN - 978-989-758-638-5
AU - Cui Q.
PY - 2022
SP - 100
EP - 105
DO - 10.5220/0012003100003625
PB - SciTePress