Title: MWCNTs decorated with Ag nanoparticles through pulse reversed current electrodeposition using a deep eutectic solvent for energy storage applications

Abstract

The massive demand for energy and the urgent need to reduce the consumption of fossil fuels has been attracting the interest of the scientific community to develop materials with even better electrochemical properties. Carbon-based materials, such as carbon nanotubes (CNTs), graphene, activated carbon, among others have received attention due to their remarkable thermal, electrical and mechanical properties. Both electrode materials and electrolyte play a significant role in any electrochemical device. Any improvement in the performance of existing electrochemical devices requires further research in both fields. CNTs are receiving special attention due to their extraordinary thermal, electrical, and mechanical properties. Combining the CNTs with metallic nanoparticles have attracted the attention of the scientific community for technological applications such as energy storage. The present work reports a ground breaking synthesis procedure to decorate MWCNT swith silver nanoparticles (Ag-NPs) via pulsed reverse deposition technique using a deep eutectic solvent (DES) based on choline chloride and glycerol as an electrolyte at room temperature, not involving any previous surface modification of MWCNTs. The Ag-MWCNTs composites were characterized by Raman spectroscopy, SEM/EDX analysis, ultrahigh-resolution STEM, in which the Z – Contrast image was collected and AFM was performed to evaluate the conductivity of the Ag-MWCNTs composites. Ag-MWCNTs composites characterization allowed to prove the successful attachment of the Ag-NPs to the MWCNTs surface. Electrochemical studies were performed using cyclic voltammetry and charge/discharge measurements using a three-electrode system. All the composite materials presented higher specific capacitance than commercial MWCNTs and the best performing material showed a 6 time increase in specific capacitance (28.50 F. g-1, against 4.70 F. g-1). In this presentation, it will be shown the most relevant results regarding the characterization of the Ag-MWCNTs composites, and its application to energy storage devices.