Stimuli Assisted Charge Transfer Dynamics for Enhanced Electrochemical Storage in Supercapacitors /batteries

Abstract

Energy storage devices require enhanced energy density without compromising power density and rapid charge-transfer kinetics. Present thesis investigates the role of external and internal stimuli in rational electrode design to regulate charge-transfer and ion-transport processes in supercapacitors and aqueous zinc-ion batteries. External magnetic fields are employed to manipulate spin ordering within electrode materials and induce magnetohydrodynamic effects in electrolytes, thereby enhancing ionic diffusion, interfacial charge transfer, and overall electrochemical performance. Magnetic-stimuli-assisted multimetallic carbonate hydroxide, flexible graphene-based magnetic sponge, and soft/hard magnetic spin junction based electrodes demonstrate enhanced charge-storage performance through the regulation of capacitive and diffusion-controlled processes. In addition to external stimuli, coordinating sites are introduced as an internal stimulus within cathode materials for aqueous zinc-ion batteries. An organic– inorganic hybrid cathode is developed, wherein synergistic interactions between redox-active organic sites and a conductive inorganic framework facilitate Zn2+ storage, accelerate charge-transfer kinetics, and improve cycling stability. Overall, thesis presented a stimuli-assisted charge-transfer regulation and rational electrode design as effective approaches for advancing high-performance supercapacitors and aqueous zincion batteries.