Quenching method introduced oxygen defect type Zn2V2O7·2H2O for long-life aqueous zinc ion batteries

• Published in: Journal of power sources 2025-01, Vol.626, p.235730, Article 235730
• Main Authors: Yang, Shengbo, Wang, Nengze, Ren, Xiaohe, Sun, Mengxuan, Pian, Tianning, Lv, Jianing, Gan, Ziwei, Yao, Xiaojun, Jia, Chunyang
• Format: Article
• Language: English
• Subjects: Oxygen vacancy; Quenching; Vanadium oxide; Zinc ion battery; Zn2V2O7
• ISSN: 0378-7753
• DOI: 10.1016/j.jpowsour.2024.235730

Cost-effective and environment-friendly aqueous zinc ion batteries (AZIBs) are ideal for emerging energy storage. Focusing on enhancing the rate performance and cycling stability of AZIBs, various metal oxides and compounds as cathode materials have drawn extensive attention. The development of high-performance AZIBs cathode materials requires concentrating on the Zn2+ intercalation strategy and exploring new materials more suitable for Zn2+ intercalation to ensure more stable Zn2+ storage. Additionally, a straightforward synthesis process considering economic effects and cost issues is essential. Herein, we introduce abundant oxygen vacancies on/near the surface of V2O5 by quenching at high temperatures to provide more insertion sites for Zn2+. Then, Zn2V2O7·2H2O with oxygen vacancies is synthesized by reacting V2O5 with ZnCl2 through stirring and subsequent hydrothermal treatment (named QH ZVO). QH ZVO has a tunnel-like structure for stable Zn2+ storage, combined with oxygen vacancy defects, enriches Zn2+ storage quantity. Density functional theory simulations show that the quenching induced oxygen vacancy narrows the energy band gap of QH ZVO and accelerates electron transfer. The maximum specific capacity reaches 78.34 mAh g−1 at 15 A g−1 with 74.47 % capacity retention after 15,000 cycles. This work offers a new approach for efficient zinc storage and enhances the electrochemical stability of AZIBs. [Display omitted] •Quenching introduces oxygen vacancies that improve the storage capacity of Zn2+.•The microstructure of nanobelts improves the transport efficiency of Zn2+.•The stable tunnel structure of Zn2V2O7 benefits the insertion/extraction of Zn2+.•The resulting cathode material achieves high cycling performance.