Revealing Kinetics Process of Fast Charge-Storage Behavior Associated with Potential in 2D Polyaniline

Clarifying the electrode kinetics and thermodynamic processes of 2D materials in electrochemical energy-storage system becomes an important topic, especially for the system with complex and interlaced electrochemical processes. One single analytical method can hardly describe the diffusion-controlled and interface-reaction-controlled process. Hence, the tungstate-linked polyaniline, a novel 2D conductive polymer with obvious Faradaic reaction, is introduced, as the research object. Based on the multi-scan rate cyclic voltammetry data, the applicable rules of different electrochemical kinetic treatment methods are proved effectively: the rate fitting equation based on theoretical capacitance calibration is more suitable to describe the kinetic behavior of interface-reaction-controlled process, while the power-law relationship based on the b value is more reasonable to study the diffusion-controlled process. Moreover, the higher capacitance of the electrode materials in acidic electrolyte is emphasized via in situ electrochemical testing techniques. Proton intercalation and participating in the redox reaction can obviously accelerate the electrode process. The developed multidimensional assessment method is superior in more accurate analysis of the kinetics of electrochemical energy-storage devices.