Electrochemical Kinetics of Layered Manganese Phosphate via Interfacial Polypyrrole Chemical Binding

Graphical Layer by layer : The electrochemical kinetics of layered manganese phosphate are improved via interfacial polypyrrole chemical binding for electrochemical supercapacitor application. The major limitation of low-cost and high-safety aqueous manganese-based materials for electrochemical energy storage is largely hampered by their poor cyclic stability, usually caused by the manganese dissolution and interfacial kinetics. Herein, we synthesized a manganese phosphate material via interfacial polypyrrole chemical binding, with unique structural properties for aqueous supercapacitor application. It exhibited higher specific capacitance, remarkable rate performance and better cycle stability compared to bare manganese phosphate. In contrast with interfacial polypyrrole coating on manganese phosphate nanosheets, the polypyrrole could form a Mn−N bond with the manganese phosphate, indicating stable chemical binding. Thus, the appropriate interfacial chemical binding is an efficient strategy to improve the nanostructure stability and electrochemical kinetics of manganese-based materials for aqueous electrochemical energy storage.