Studying δ-MnO2/reduced graphene oxide composite cathode in a low-temperature and high-voltage-tolerant hybrid electrolyte for aqueous Mg-ion batteries. (1st April 2023)

• Record Type: Journal Article
• Authors: Tsai, Yi-Ru; Chen, Ting-Yu; Yang, Zhong-Qi; Tsai, Cheng-Che; Huang, Yu-Ting; Anuratha, Krishnan Shanmugam; Lin, Tsung-Wu; Sofer, Zdenek; Lin, Jeng-Yu
• Is Part Of: 2D materials. Volume 10:Number 2(2023)
• Publication Date: 2023-04-01
• Subjects: δ-MnO2 -- reduced graphene oxide -- composite cathode -- hybrid electrolyte -- aqueous Mg-ion batteries; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/acb278
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Optimization of the aqueous electrolyte concentration is a significant issue in the development of high-performance aqueous rechargeable magnesium ion batteries (MIBs). In this study, a novel magnesium ion-based hybrid electrolyte composed of 2 M magnesium sulfate (MgSO4 )/2 M acetate (MgOAc) was designed, and its corresponding physiochemical properties were systemically investigated by simply tuning their molar ratios. Additionally, a δ -MnO2 /reduced graphene oxide (rGO) composite cathode material was successfully synthesized and delivered a high specific capacity and excellent rate capability in the optimized hybrid electrolyte. The as-fabricated device based on the δ -MnO2 /rGO composite cathode exhibited a high operating voltage of up to 2 V and delivered a maximum energy density of 29.8 Wh kg −1 at the power density of 823 W kg −1 . More importantly, the device showed impressive discharge capacity and excellent cycling stability even at the low temperature of −20 °C. In view of the outstanding electrochemical properties of the δ -MnO2 /rGO composite cathode in an optimized hybrid electrolyte of MgSO4 /MgOAc, it could be regarded as a novel prototype for low-cost aqueous MIBs.