The 7th International Conference on New Energy and Future Energy Systems (NEFES 2022)

Abstract: Emergence of sustainability as the new normal and consequent concerns over material sustainability for various industrial sectors accelerated materials discovery process from renewable sources. Energy storage become one of the dominant industries currently and most of the high performing energy storage devices such as lithium-ion batteries use expensive mined materials as electrodes with enormous processing and value addition. Biomass derived carbon has been suggested as a possible material for energy storage, however, they mainly suffer from lower performance indicators. We have explored augmenting properties of biomass carbon with small amounts (~5 – 10 wt.%) of metals or metal oxides to enhance the charge storage parameters in lithium-ion capacitors, battery–supercapacitor hybrids, and electrochemical capacitor storage modes besides developing eco-friendly and green routes for their processing using physical means than chemical methods. Four strategies were adopted: (i) enhancing the charge storage sites by filling large voids in porous carbon by hierarchical 3D nanoflowers or composite nanostructures, (ii) developing a thin metal oxide film over porous carbon surface through a simultaneous activation and coating process, (iii) developing a thin metal film over porous carbon, and (iv) green reduction of graphene oxide to reduced graphene oxide by means of physical methods than chemical ways. Several advanced carbon structures are thereby synthesized; in supercapacitive charge storage mode they gave charge storability of ~60% of lithium battery and ~10 times more power capability than lithium battery. Only 10% metal compositions could boost up the energy storage capabilities dramatically. Promising green processing routes are also developed which avoid large scale toxic chemicals for developing advanced materials.