Preparation method and application of a ferric phosphate material

Abstract

The present disclosure provides a preparation method of iron phosphate material, and relates to the field of lithium ion battery positive electrode material, which comprises the following steps: mixing an organic phosphorus solution with humic acid to obtain a mixed solution; adding a high ferrate-containing solution into the mixed solution to obtain a trivalent iron-containing solution; adjusting the pH of the trivalent iron-containing solution to generate a precipitate, and obtaining a precipitate after filtration; drying the precipitate and removing the crystal water to obtain an anhydrous FePO4 material. The present disclosure uses high ferrate to oxidize organic phosphorus, and the high ferrate is reduced into trivalent iron itself, which provides an iron source and acts as an oxidizing agent. In the oxidation process, humic acid is introduced to form a competitive oxidation relationship with organic phosphorus, and the high ferrate is activated into a higher-oxidation iron-based intermediate. After the oxidation of humic acid, the electronegativity is enhanced to adsorb iron ions and play a dispersion role, preventing the generated iron phosphate from agglomerating, and the particle size is uniform, which is conducive to improving the electrical properties of the subsequently prepared lithium iron phosphate.

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