Carbon based electrodes are playing a crucial role in the development of energy storage devices. This development is important for India, especially for states such as Uttar Pradesh, combined states of Andhra Pradesh and Telangana, which are the first and second largest producers of corn in the country respectively. They produce a large amount of corn husk waste, much of which waste is currently burnt as its potential to be converted to valuable electrode material is not harnessed owing to lack of awareness, expertise and technology.
Research by IIT-H on affordable and efficient methods can enable this conversion, which would trigger the cascade of additional earning opportunities for the corn-farmer and provision of a sustainable energy source.
Led by Atul Suresh Deshpande, associate professor, department of materials science and metallurgical engineering, IIT-H, in collaboration with TN Rao, associate director, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, the research paper detailing the synthesis procedure and the electrochemical performance of the material produced has been recently published in the reputed peer-reviewed Journal of Power Sources.
Carbon based electrodes are typically derived from expensive, high purity precursors such as polymers, organic precursors, high purity gases using various methods. The production of carbon electrodes from biomass is a simpler straightforward process. In collaboration with ARCI (Hyderabad), the IIT Hyderabad team has developed activated carbon electrodes using simple materials – Corn husk and KOH.
“Activated carbon electrode material with porous sheet-like morphology has been prepared using corn husk through carbonization followed by KOH activation. Due to the low-cost precursors and simple processing method, this process of producing activated carbon can be easily adapted for large-scale commercial production,” said Deshpande.
To obtain the high surface area activated carbon with porous sheet-like morphology from corn husk, the researchers added KOH as an activating agent. KOH helps in the formation of sheet-like morphology. The synergy of morphology and high specific surface area (1378 m2 g-1) improve the storage capacity of the activated carbon electrode material.
The storage capability of activated carbon samples tested by using high-operating voltage electrolyte (1M tetraethylammonium tetrafluoroborate (TEABF4) in acetonitrile (AN)). This electrode showed better electrochemical performance (High energy density (20 Wh kg-1) and high-power density (681 W kg-1) at 1 A g-1) than electrodes in conventional supercapacitors.