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

Abstract 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 FeF 3 ⋅0.33H 2 O cathode. Carbon with abundant channels combine with FeF 3 ⋅0.33H 2 O 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 FeF 3 ⋅0.33H 2 O. 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 FeF 3 ⋅0.33H 2 O. Moreover, the capacity still maintains at 101 mAh g −1 after 500 times charge/discharge at a current density of 5 C.