Towards Promotion of Graphene/Titania‐Based Electrode via Ultrafast and Self‐Expansion Reduction for Li‐ion Battery

Ultrafast Reduced Graphene Oxide: Ultrafast and self-expansion reduction reaction induces self-expansion of reduced graphene oxide free-standing films through rapid heating providing abundance of cavities/empty spaces to alleviate volume change during charge/discharge process resulting in boosted storage and conversion response of the Li-ion battery free of non-active agents (765 mAh g⁻¹ at 0.05 A g⁻¹) and accelerated Coulombic efficiency.

Abstract

In this study, a facile strategy to promote electrochemical performance of free-standing Li-ion battery electrode composed of titanium dioxide (TiO₂) via composite formation with reduced graphene oxide (RGO) using ultrafast and self-expansion reduction reaction (USER) was proposed. This approach induced self-expansion through rapid heating providing abundance of cavities/empty spaces to alleviate volume change during charge/discharge process resulting in boosted storage and conversion response of the system (765 mAh g⁻¹ at 0.05 A g⁻¹) and accelerated Coulombic efficiency. Detailed electrochemical, microscopic and structural analyses (ex-situ) of the film prove that this internal expansion delivers enhanced ionic diffusion and shielding material from volume changes during charge/discharge process. Therefore, we believe that this simple and very fast strategy offers a venue to overcome one of the main bottleneck in promotion of electrochemical performance of other active materials which are sensitive to volume expansion during lithiation/delithiation process.

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