Black Phosphorus Self‐Catalyzed In Situ Interfacial Cross‐Linking Reactions Enabling Low‐Temperature Carbon Coating for High‐Stable and High‐Capacity Lithium Storage

Abstract Black phosphorus (BP), a promising high‐capacity anode material for lithium‐ion batteries, faces critical challenges of poor electrical conductivity and severe electrode pulverization. Traditional carbon coating strategies are often conducted under high‐temperature (over 700 °C) or oxidative conditions that are not suitable for BP due to its low sublimation temperature (400 °C) and high oxidation susceptibility in air/moisture. In this work, by utilizing self‐catalysis effect of BP, we propose a low‐temperature carbon coating strategy for BP anodes toward high‐stable and high‐capacity lithium storage. The strategy is realized by a two‐step approach including interfacial electrostatic assembly of carbon quantum dots (CQDs) on BP nanosheets, followed by BP self‐catalyzed in situ interfacial cross‐linking of CQDs, forming a continuous carbon layer on BP (BP@CL). DFT calculations reveal that BP self‐catalysis significantly reduces the energy barriers of CQDs cross‐linking reactions, while finite element simulations demonstrate that the carbon layer effectively mitigates lithiation stress of BP@CL (above 51% reduction). The optimized BP@CL composite anode exhibits exceptional cycling stability with 87.3% capacity retention after 500 cycles at 0.2 A g −1 , significantly outperforming that of pristine BP. The developed mild carbon coating method with BP self‐catalysis provides a new opportunity for designing advanced BP‐based electrodes in energy storage applications.