An ecofriendly and universal strategy to balance the active sites and electrical conductivity of biomass-derived carbon for superior lithium storage

摘要

Biomass-derived hard carbons are one of the most promising anode materials for lithium-ion batteries. However, their further development is restricted by their trade-off between the capacity and rate properties. It is of great importance to explore durable and conductive carbon anodes. In this study, a facile strategy is developed to adjust the active sites and conductivity of biomass-derived carbon via B, O dual doping under low-temperature pyrolysis, which shows a high reversible capacity (469 mA h g(-1)@0.2 A g(-1)), remarkable rate capability (268 mA h g(-1)@6 A g(-1)), and superior stability of the as-prepared BO-CNSs. We reveal the underlying origin of the boosted electrochemical performance that the introduction of B can generate ample B-O-C interface bonds and facilitate graphitization, thus improving the conductivity of the carbon framework. Meanwhile, the O dopant affords abundant active sites and thus garners additional storage capacity with high capacitance contribution. This work suggests a straightforward way to overcome the pain spot of hard carbon derived from biomass and expedite its commercialization.

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