羟基磷酸铁铵的制备与表征

Preparation and characterization of spheniscidite

采用硫酸亚铁和磷酸为原料,在尿素存在的条件下,水热合成得到高纯度的羟基磷酸铁铵。研究发现,反应温度不同得到的羟基磷酸铁铵的结晶度会有所不同,形貌差异较大。利用XRD、SEM、TG-DTA和红外分析等手段对制备的样品组成、结构、晶型和形貌做分析表征,分析了羟基磷酸铁铵在加热过程中的相变过程。结果表明,在静态羟基磷酸铁铵中,磷酸和铁具有固定的化学计量比,经高温煅烧后得到高纯度磷酸铁,可应用其制备锂离子电池正极材料磷酸铁锂的前驱体,且此法合成工艺简单,具有良好的工业应用潜质。

Spheniscidite of high-purity was synthesized in the presence of urea by hydrothermal method using ferrous sulfate and phosphoric acid as raw materials.Spheniscidites with different crystallinity and morphology were obtained by changing the reaction temperature,and the ferric phosphate was ultimate product after the calcination.The composition,structure,crystal shape and morphology of the synthesized spheniscidites were systematically characterized and analyzed by XRD,SEM,TG-DTA and infrared analysis.The phase transition process of spheniscidite during heating was analyzed.The results showed that phosphoric acid and iron had a fixed stoichiometric ratio in the static spheniscidite,and iron phosphate was obtained with high purity when synthesized spheniscidite was calcinated at high temperature,which could be used as a precursor of cathode material for lithium ion batteries and the method had simple synthesis process and good industrial application potential.