High-Value\nResource Utilization of Steel Waste to\nPrepare Uniform Micronano LiFePO<sub>4</sub>/C Cathode Material

Steel\nslag is a promising secondary resource necessitating recycling\nand high-value utilization. This study innovatively converted steel\nslag into micronano FePO<sub>4</sub> and well-performing LiFePO<sub>4</sub>/C through a selective two-step leaching process followed\nby fast coprecipitation in HMCRR under superior mass transfer, and\na subsequent in situ carbothermal reduction afterward, thereby realizing\na waste-to-resource conversion pathway. Besides, a metal leaching\nmechanism was proposed based on comprehensive slag composition analysis,\naffirming the process selectivity. Thermomechanical analysis for precipitation\nunderscored the importance of controlling reaction pH to prevent the\nformation of impure sediments. Leveraging efficient leaching and superior\nmass transfer during precursor preparation, the further-made carbon-coated\nLiFePO<sub>4</sub>/C derived from steel slag exhibited favorable morphology\nand enhanced discharge capacity, especially at high rates, owing to\nfast ion diffusion kinetics, minimized Li<sup>+</sup> migration distance,\nand improved structure stability. Notably, the discharge capacity\ncould reach 167.44, 153.56, and 119.62 mAh/g at 0.1, 1, and 10 C,\nrespectively.