Mass Production of Metallic Fe@Carbon Nanoparticles with Plastic and Rusty Wastes for High-Capacity Anodes of Ni-Fe Batteries

The recycle/reuse of wastes is significant for green and sustainable development of our society. Herein, we present the mass production of Fe@C nanoparticles (NPs) with plastic and rusty wastes for making high-capacity anodes of Ni-Fe batteries. The total conversion is achieved by a facile one-step chemical vapor deposition process, where plastics decomposition offers rich hydrocarbons and iron rust-derived Fe₂O₃ are reduced to Fe NPs, in situ launching the catalytic growth of carbon (C) shells on their surfaces. All Fe NPs are thereby tightly sealed by C layers, whose thickness can be controlled by tuning the reaction time. Benefiting from superb reactivity/conductivity of the Fe core and good stability/robustness of the C shell, such unique Fe@C hybrid configurations exhibit a high delivered capacity (Max. value: 405.2 mA h g^-1), excellent rate performance, and superb cyclic stability (91.9% capacity retention after 4000 cycles). The further assembled full-cell (-)Fe@C//NiO@C(+) devices can deliver impressive specific energy density (138 W h kg^-1) and rate capability (14.5 kW kg^-1), verifying their great potential in real applications. This paradigm work may guide us to massive and smart evolution of disposable/useless wastes into useful materials for energy-related applications.