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Updated: Sep 16, 2025
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Discretizing Cobalt Spin-Orbitals through Tuning the Crystal Symmetry for Zinc-Air Batteries
Yi Jiang1, Ruilin Liang1, Changshun Wang2
1Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Waterloo Institute for Sustainable Energy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
None:
Regulating the electron-spin state of metal active sites is a rarely cultivated topic for oxygen electrocatalysis. Here, a dual-ligand metal-organic framework (DM) is developed to endow Co sites with D4h crystal symmetry, reconfiguring their orbital degeneracy and electron spin state. The discretized spin-orbital configuration offers the accelerated transformation of the O-related intermediate by accepting electrons via partial d-orbital occupation and mediation of the hydroxyl adsorption strength through electron donation to O p-orbitals. With this orbital flexibility, Co sites serve as "Lewis acid-base" pairs that hasten O redox of oxygen during Zn-air battery cycling, which is validated by operando X-ray absorption spectroscopy and theoretical modeling. Compared to counterparts with different crystal symmetries, Zn-air batteries using the DM electrocatalyst showcase reduced charge-discharge voltage gap and high round-trip energy efficiency at high areal capacity.
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