A carbon-coated spinel zinc cobaltate doped with manganese and nickel as a cathode material for aqueous zinc-ion batteries

ZnNi_0.5Mn_0.5CoO₄@C with a spinel structure was made via a sol–gel and high-temperature sintering process exhibits excellent electrochemical performance due to reversible multivalence redox transitions (Co⁴⁺/Co³⁺, Ni⁴⁺/Ni³⁺/Ni²⁺, and Mn⁴⁺/Mn³⁺).