Tuning Proton Insertion Chemistry for Sustainable Aqueous Zinc-Ion Batteries

Abstract

Rechargeable aqueous zinc-ion batteries (ZIBs) have emerged as an alternative to lithium-ion batteries due to their affordability and high level of safety. However, their commercialization is hindered by the low mass loading and irreversible structural changes of the cathode materials during cycling. Here, a disordered phase of a manganese nickel cobalt dioxide cathode material derived from wastewater via a coprecipitation process is reported. When used as the cathode for aqueous ZIBs , the developed electrode delivers 98% capacity retention at a current density of 0.1 A g-1 and 72% capacity retention at 1 A g-1 while maintaining high mass loading (15 mg cm-2). The high performance is attributed to the structural stability of the Co and Ni codoped phase; the dopants effectively suppress Jahn-Teller distortion of the manganese dioxide during cycling, as revealed by operando X-ray absorption spectroscopy. Also, it is found that the Co and Ni co-doped phase effectively inhibits the dissolution of Mn2+, resulting in enhanced durability without capacity decay at first 20 cycles. Further, it is found that the performance of the electrode is sensitive to the ratio of Ni to Co, providing important insight into rational design of more efficient cathode materials for low-cost, sustainable, rechargeable aqueous ZIBs. In the pursuit of sustainable energy solutions, the potential of manganese nickel cobalt dioxide materials for aqueous zinc-ion batteries are presented. By addressing the Jahn-Teller distortion through Ni and Co doping, the presented cathode material sheds light on achieving enhanced battery performance. These findings not only underline the importance of material engineering but also suggest a roadmap for eco-friendly battery solutions derived from wastewater processes.image