Black Phosphorus Covalent Bonded by Metallic Antimony Toward High‐Energy Lithium‐Ion Capacitors

Abstract Black phosphorus (BP) has been recognized as an alluring fast‐charging anode for batteries/supercapacitors due to its substantial theoretical capacity, propitious lithiation potential, and large interlayer spacing. Nonetheless, it is encumbered by challenges of low electronic conductivity, momentous volume expansion (≈300%), and pernicious shuttle effect induced by soluble polyphosphides. Here a BP heterostructure covalent bonded by metallic antimony (Sb) is showed, which can promote the reaction dynamics of BP and greatly ameliorate the cycling performance. Robust P─Sb covalent bonds are methodically engineered to regulate the Femi level, endowing enhanced electronic conductivity. The in situ generated Li₇SbO₆ ionic conductor in the P/Sb interface during the lithiation process ensures the fast Li⁺ transport. Furthermore, Sb offers strong anchoring and chemical adsorption capability on soluble lithium polyphosphides, preventing the shuttle issue. As a result, a lithium‐ion capacitor (LIC) full‐cell based on Sb@BP/C anode demonstrates a superior energy density of 174.3 W h kg⁻¹ and a power density of 23.7 kW kg⁻¹, as well as exceptional reversible capacity retention. This work provides insights into the regulation of reaction kinetics and chemical adsorption capability of BP, offering guidance for designing high‐capacity and stable BP‐based anodes.