Iron Fluoride Nanoparticles Embedded in a Nitrogen and Oxygen Dual-doped 3D Porous Carbon Derived from Nori for High Rate Cathode in Lithium-ion Battery

A unique nitrogen and oxygen dual-doped three-dimensional porous carbon derived from nori which can be produced in large-scale is used as conductive matrix to solve the problem of low conductivity of FeF₃⋅0.33H₂O cathode. Carbon with abundant channels combine with FeF₃⋅0.33H₂O nanoparticles to form a micro-nanostructure material. The combination of small nanoparticles and highly conductive three dimension porous carbon skeleton forms a high-speed ion and electron transport network which benefit the Li-storage performance of FeF₃⋅0.33H₂O. The as-prepared composite possess a capacity of 170, 157, and 104 mAh g⁻¹ at 1 C, 2 C, and 20 C in lithium-ion batteries which is much better than bulk FeF₃⋅0.33H₂O. Moreover, the capacity still maintains at 101 mAh g⁻¹ after 500 times charge/discharge at a current density of 5 C.