摘要
Development of anode materials of high capacities, rate capability, and cycling stability is critical for lithium ion capacitors (LICs). Composite electrode design, combining advantages of constituent component materials, is a promising approach for the purpose. Porous core-shell B-doped silicon-carbon spheres, B–Si@1RFC, of small sizes (150 nm) and high specific capacities are successfully synthesized with a one-pot method, followed by carbonization, magnesiothermic reduction, and B-doping, to be composited with reduced graphene oxide (rGO) porous structure of excellent structural and electrical properties to serve as an outstanding anode material, B–Si@1RFC/rGO, for LICs. The LIC, assembled by coupling the B–Si@1RFC/rGO anode with a glucose-derived carbon nanosphere cathode of ultrahigh specific surface areas (1947 cm 2 g −1 ) and pore volumes (2.04 cm 3 g −1 ), delivers a high energy density of 149 Wh kg −1 at a power density of 0.328 kW kg −1 and maintains a decent energy density of 82.1 kW kg −1 at a high power density of 49.3 kW kg −1 , together with an excellent cycling stability of retaining 74.4% of the initial energy density after 10,000 cycle operations at 5 A g −1 .