A chemical–mechanical coupling effect induced by charge distribution engineering yields a long-lived phosphorus anode for lithium-ion batteries†
Abstract
The phosphorus anode has received extensive attention owing to its high theoretical specific capacity, moderate working potential and low cost. However, the unreconciled conflicts between high capacity and high volumetric changes and accompanying sluggish kinetics seriously hinder the utilization of phosphorus for lithium-ion storage. Herein, we propose a unique organic/inorganic phosphorus/polyphthalocyanine/graphene oxide composite to achieve a stable phosphorus-containing anode with ultra-long cycle life. The configured heterogeneous interface is demonstrated to be feasible to accelerate the electron/ion transfer accompanied by enhanced kinetics. Simultaneously, it is endowed with the function of electron giving and shunting, which enables the spontaneous chemical splitting of LiPF6 electrolyte without an exterior potential driving force, altering the formation process of the solid electrolyte interface film and simultaneously suppressing the volumetric changes as well. This unconventional dual heterojunction interface results in a long-lived phosphorus composite electrode with a high coulombic efficiency close to 100% after 10 000 cycles at a high current density of 5 A g−1.