Boosting Reversibility and Stability of Zn Anodes via Manipulation of Electrolyte Structure and Interface with Addition of Trace Organic Molecules. Issue 38 (17th August 2022)

• Record Type: Journal Article
• Authors: Huang, Haiji; Xie, Dongmei; Zhao, Jiachang; Rao, Pinhua; Choi, Won Mook; Davey, Kenneth; Mao, Jianfeng
• Is Part Of: Advanced energy materials. Volume 12:Issue 38(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-17
• Subjects: AZIBs -- corrosion -- electrolyte additives -- solvation structure -- zinc dendrites; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202202419
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: The practical application of aqueous zinc‐ion batteries (AZIBs) is significantly limited by poor reversibility and stability of the Zn anode. Here, the first time addition of trace organic gamma butyrolactone (GBL) is reported to a typical ZnSO4 electrolyte to controllably manipulate the electrolyte structure and interface. Judiciously combined experimental characterization and theoretical computation confirm that the GBL additive weakens the bonding strength between Zn 2+ ion and solvated H2 O and rearranges the "Zn 2+ −H2 O−SO4 2– GBL" bonding network to reduce water activity and suppress corrosion and side products. The GBL molecules preferentially absorb on the surface of the Zn anode to give a uniform and compact Zn deposition. As a result, the Zn anode is boosted to run over 3105 cycles (6210 h) with average Coulombic efficiency of 99.93% under 1 mA cm –2 and 1 mAh cm –2, and exhibit stable cycling for 1170 h under harsh testing conditions of 10 mA cm –2 and 10 mAh cm –2 . Additionally, the Zn–MnO2 full cells using the ZnSO4 –GBL electrolyte exhibit a high capacity of 287 mAh g –1 at 0.5 A g –1 and good capacity retention of 87% following 400 cycles. These findings will be of immediate benefit to design low cost AZIBs for clean energy storage. Abstract : Trace organic molecules are used to controllably manipulate an aqueous electrolyte structure and interface. Addition of gamma butyrolactone (GBL) rearranges the "Zn 2+ −H2 O−SO4 2– −GBL" bonding network of the aqueous electrolyte and alters the interface via the absorbtion of GBL on the Zn surface, reducing water activity, suppressing corrosion and formation of by‐products, and resulting in a uniform and compact Zn deposition.