A novel method whose starting materials was Fe–P waste slag and CO₂ using a closed-loop carbon and energy cycle to synthesize LiFePO₄/C materials was proposed recently. In the first step, Fe–P slag was calcinated in a CO₂ atmosphere to manufacture Fe₃(PO₄)₂, in which the solid products were tested by XRD (X-ray diffraction) analysis and the gaseous products were analyzed by the gas detection method. In the second step, as-synthesized Fe₃(PO₄)₂ was further used as the Fe and P source to manufacture LiFePO₄/C materials. Also, the influence of the preparation conditions of Fe₃(PO₄)₂, including calcination time and calcination temperature, on the energy storage properties of as-obtained LiFePO₄/C was investigated. It was found that the LiFePO₄/C materials, which was synthesized from Fe₃(PO₄)₂ obtained by calcining Fe–P waste slag at 800 °C for 10 h in CO₂, exhibited a higher capacity, better reversibility, and lower polarization than other samples. The discharge capacity of as-obtained LiFePO₄/C can reach 145 mAh/g at 0.1 C current rate. This work puts forward an environment-friendly method of manufacturing LiFePO₄/C cathode materials, which has a closed-loop carbon and energy cycle.

中文翻译：

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利用 Fe-P 废渣和 CO2 合成 Fe3(PO4)2 并作为前驱体制备 LiFePO4 的新策略

最近提出了一种以Fe-P废渣和CO ₂为起始原料，利用闭环碳和能量循环合成LiFePO ₄ /C材料的新方法。第一步，将Fe-P渣在CO ₂气氛中煅烧制备Fe ₃ (PO ₄ ) ₂，其中固体产物用XRD（X射线衍射）分析，气态产物用X射线衍射分析。气体检测方法。第二步，进一步使用合成的Fe ₃ (PO ₄ ) _{2作为Fe和P源来制造LiFePO 4} /C材料。此外，还研究了Fe ₃ (PO ₄ ) ₂的制备条件（包括煅烧时间和煅烧温度）对所得LiFePO _{4 /C储能性能的影响。}研究发现，以Fe-P废渣在CO _2中800 ℃煅烧10 h得到的Fe ₃ (PO ₄ ) _{2合成的LiFePO 4} /C材料具有更高的容量、更好的可逆性和比其他样品更低的极化。所获得的LiFePO ₄ /C在0.1 C倍率下的放电容量可以达到145 mAh/g。这项工作提出了一种环境友好的制造LiFePO ₄ /C正极材料的方法，该材料具有闭环碳和能量循环。