Exploring the mechanisms of magnetic fields in supercapacitors: material classification, material nanostructures, and electrochemical properties

Abstract

In the electrochemical energy storage field, supercapacitors occupy an extremely important position and have broad development prospects. However, the method for solving the low energy density of supercapacitors is approaching a bottleneck. The application of magnetic field-assisted electrochemistry is highly desirable because it can significantly promote the design of functional electrode materials, affect the morphology and assembly of materials and provide a large specific surface area and short ion transport channels. Moreover, five main forces (magnetohydrodynamic, Lorentz force, magnetization force, magnetic torque, and the interaction between the magnetization energy and magnetic dipoles) can promote rapid interfacial charge transfer of reactants and improve material wettability, thus improving electrochemical performance. In this article, we reviewed typical strategies for designing different nanostructures and various assemblies of electrode materials to enable unique electrochemical advantages under magnetic fields. An overview of recent research advances in magnetic field-enhanced electrochemical performance in supercapacitors is presented for a representative material that is essential for energy and sustainability, including direct and indirect improvements in the performance of supercapacitors through magnetic fields. Due to their excellent performance, the underlying mechanisms are discussed. Meanwhile, the important achievements and key challenges are also discussed.