| Title: | The role of aqueous electrolytes in the electrochemical performance of calcium vanadate cathode for Zn-ion storage |
Authors: | Petrović, Tamara Vasić, Milica Milović, Miloš Bajuk-Bogdanović, Danica Mentus, Slavko Vujković, Milica |
Keywords: | Aqueous electrolytes;Calcium vanadium oxide;High Zn2+storage capacity;Proton co-insertion;Zn2+ion insertion/deinsertion |
Issue Date: | 1-Jan-2025 |
Journal: | Ceramics International |
Abstract: | In light of the growing needs for high-performing, safe, low-cost and eco-friendly energy storage systems, herein, the CaV2O6–based composite (CaVO400/C) is studied as a potential cathode host for the Zn2+ion storage in aqueous rechargeable zinc-ion batteries (AZIBs). The CaVO400/C composite, synthesized via malonic acid-assisted solution combustion method (including calcination at 400 °C), is subjected to thorough electrochemical and structural analyses. Its electrochemical performance in a half-cell configuration is evaluated in three different 3 M zinc aqueous electrolytes: Zn(NO3)2, ZnSO4and ZnCl2. Over a large number of CV cycles, the electrochemical behaviour of the composite is markedly different depending on the electrolyte (anion type and pH value). The most favourable electrochemical behaviour is observed in Zn(NO3)2, where high and quite stable redox activity is retained over 400 cycles. In contrast, the performance in ZnSO4is diminished by dissolution of active vanadium species during initial cycling (pH = 4) or prolonged cycling (pH = 2), while after cycling, the formation of Zn4(SO4)(OH)6·nH2O phase is detected on the electrode. The ZnCl2electrolyte leads to a complete loss of activity due to vanadium consumption: for pH = 5 - caused by irreversible transformation of the electrochemically active phase into the inactive one, Zn3(OH)2V2O7·2H2O, and for pH = 2 – caused by consecutive formation and dissolution of Zn3(OH)2V2O7·2H2O. It is suggested that formation of the proton-doped vanadium oxide species as the active phase, during cycling in Zn(NO3)2electrolyte, facilitates the efficient Zn2+storage in the CaVO400/C electrode, enabling insertion/deinsertion specific capacity of ∼167/145 and ∼119/115 mAh g−1at 500 and 2000 mA g−1, respectively, in a half-cell configuration. |
URI: | https://dspace.ffh.bg.ac.rs/handle/123456789/2525 |
ISSN: | 02728842 |
DOI: | 10.1016/j.ceramint.2025.10.229 |
| Appears in Collections: | Journal Article
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