氧化石墨烯在二水磷酸铁复合前驱体制备中的作用

摘要

Graphene/FePO4·2H2O composite precursors are prepared by homogeneous precipitation method with Fe (NO3)3·9H2O, NaH2PO4·2H2O and H3PO4, added in graphene oxide (GO). Results show that GO can change the morphology of FePO4·2H2O powders from flocculent to round. Then the round powders are con-centrated by filtration, and raw materials are dropped in the products to make the powders re-grow. The final powders are spherical with homogeneous particle size ( D50 = 4.220 μm, the tap density is 1.31 g/m3). The analysis of XRD, FT-IR and Raman data shows that GO is mainly reduced to grapheme which has great value for the preparation of graphene/FePO4·2H2O composite precursor.%以Fe（NO3）3·9H2O、NaH2PO4·2H2O、H3PO4为原料，添加氧化石墨烯（Graphene oxide， GO），采用均相沉淀法制备石墨烯/二水磷酸铁复合前驱体（Graphene/FePO4·2H2O），以期用于制备石墨烯/LiFePO4复合正极材料.结果发现，GO的添加可使FePO4·2H2O前驱体形貌由团聚的絮状转变为分散的类球状；对类球状粉体过滤浓缩后，再进行原料的滴加操作，使类球状粉体二次生长，产物为规则的球状粉体，且粒度分布均匀，分散性好，D50=4.220μm，振实密度达1.31 g/m3.粉体的XRD、FT-IR及Raman分析结果表明，前驱体制备中添加的GO在反应过程中已基本还原为石墨烯，这对于高密度球状石墨烯/磷酸铁复合前驱体的制备具有重要的应用价值.