Pseudocapacitance: Tuning Electrochemical Properties

Recently, advanced electrochemical energy storage technology has come to require both high energy and power densities. Pseudocapacitance originates from the charge transfer reaction across the electrochemical interface and depicts higher capacitance than capacitors and faster electrochemical kinetics than traditional batteries, providing the opportunity to fulfill this goal. However, due to the intrinsic poor electrical conductivity, or inadequate structural stability, the rate performance and cycling stability of pseudocapacitive materials are still unsatisfactory. Thus, various strategies have been proposed to tune the electrochemical performance of pseudocapacitive materials for achieving both high energy and power. In this chapter, we highlight some recent works in developing pseudocapacitive materials for electrochemical energy storage systems. By introducing the research advances of both “intrinsic” and “extrinsic” pseudocapacitive materials, tune strategies such as nanostructure design, doping, introducing oxygen vacancies, interlayer engineering, heterostructure engineering, etc., have been carefully discussed. We hope this work will be of directive significance for the design and fabrication of high-performance electrode materials.