High-performance alkaline aqueous zinc battery enabled by nickel-cobalt-tellurium materials

Abstract

The capacity and cycling performance of cathodes are key factors in aqueous zinc batteries (AZBs). The search for cathode materials with long cycle lives and high specific capacities is of paramount importance. In this study, a bimetallic telluride with a hollow polyhedral structure was synthesized using a hydrothermal method followed by vapor deposition. This composite exhibits high conductivity, facilitates rapid diffusion of electrolyte ions into the interior, and accelerates redox reactions, thereby enhancing electrochemical performance. The CoTe2-NiTe2 electrode demonstrates an impressive specific capacity of 188.8 mAh/g at 1 A/g, highlighting its efficiency in storing a significant amount of charge per unit mass during electrochemical reactions. The assembled CoTe2-NiTe2//Zn battery shows favorable capacity retention (76.4%) after 10000 cycles. The energy density is remarkably high, reaching 290.3 Wh/kg, while maintaining a power density of 1.75 kW/kg. This bimetallic telluride strategy holds great promise as an alternative cathode for AZBs.