Author(s): Chen, D (Chen, Duo); Lu, MJ (Lu, Mengjie); Wang, BR (Wang, Boran); Chai, RQ (Chai, Ruiqing); Li, L (Li, La); Cai, D (Cai, Dong); Yang, H (Yang, Hang); Liu, BK (Liu, Bingke); Zhang, YP (Zhang, Yupu); Han, W (Han, Wei)

Source: ENERGY STORAGE MATERIALS Volume: 35 Pages: 679-686 DOI: 10.1016/j.ensm.2020.12.001 Published: MAR 2021

Abstract: Vanadium-based cathodes for zinc-ion batteries (ZIBs) hold a great promise for next-generation energy storage systems due to their amazing diversity, relatively high capacity and excellent stability. Unfortunately, the specific capacity of current vanadium-based electrodes is intrinsically limited by zinc site density in crystal structures, probably attributing to the ignore of exception energy storage mechanism in cationic insertion/extraction. Herein, a new energy storage mechanism in the vanadium oxide-based ZIB system via cationic conversion reactions was demonstrated for the first time. At the force of electric and weak acid conditions, the oxygen-doped vanadium nitride (O-VN) cathode was firstly electrochemically oxidized into vanadium oxide and vanadium cations via in-situ activation; the cations would be reduced to V2O3 that depositing on the surface of the electrode in the discharge process; and subsequently the V (III) species could be oxidized back to the cations dissolving into electrolyte upon charging. First-principle density functional theory (DFT) calculations confirm the reversible characteristics of these reactions. Owing to these cationic conversion reactions together with contributions from zinc ion de/intercalation, the O-doped VN cathode delivered an ultrahigh discharge capacity of 705 mAh g(-1) at 0.2 A g(-1). This work continues to develop the energy storage mechanism of vanadium-based cathode and reveals the arrival of a new era for high-capacity ZIBs.

Accession Number: WOS:000621366200002

Author Identifiers:

Author        Web of Science ResearcherID        ORCID Number

Li, La         G-7527-2018         0000-0001-7355-0407

ISSN: 2405-8297

Full Text: https://www.sciencedirect.com/science/article/pii/S2405829720304645?via%3Dihub