Developing Hybrid Aqueous Li/Na-Ion Capacitors by Electrodes Synthesized by Facile Recycling and Reuse Process: Waste to Wealth

Abstract

The explosive evolution of industrialization and technologies has grabbed eyeball attention inthe current scenario for improving the living standard of the human beings irrespective of the threat and risk possessed by the environment. So to overcome this catastrophe, there has been a significant focus on progressive development of electrochemical energy storage and conversion systems to resolve the intermittency nature of renewable energy sources. The electrochemical energy storage devices such as batteries and supercapacitors have been relied upon the ability to store the charge in the wide potential region with high Coulombic efficiency and long-term stability. However, transition metal oxides are well known, for their high theoretical specific capacity but suffer from low electronic conduction and capacity fading during cycling. To address these shortfalls metal oxides are usually, embedded within a conductive carbon-based matrix (for instance graphene). The use of graphene would afford easy pathway for electron movement and increases the surface area for higher interaction of active electrode materials with electrolyte. Subsequently, graphene based transition metal oxides composites have attracted active research pursuits in synthesizing the low cost effective electrode materials for energy storage devices. And if graphene is recycled and reused then it’s very much cheap and efficient electrodes for hybrid energy storage devices. In this work, electrode materials are developed by facile and economic approach with an aim to achieve improved electrochemical activity. The conversion of utilized electrode materials (e-waste) to efficient graphene electrodes (wealth) is validated in this research. The challenges in this work are (i) recycling pure samples, (ii) resynthesizing the graphene and tuning its layers, (iii) stability and efficiency of electrode materials, (iv) optimization of electrode materials and (v) practical demonstration of hybrid-ion capacitors. The fascinating part of the research finding is both the electrode materials are derived via. recycling, for which device can be promise to be sustainable and clean energy. The details will be presented in ECS conference. Such scheme could serve as precedent to the development of potential electrode materials for energy storage devices.