LiFePO₄@C/reduced graphene oxide (rGO) hierarchical microspheres with superior electrochemical activity and a high tap density were first synthesized by using a Fe³⁺‐based single inorganic precursor (LiFePO₄OH@RF/GO; RF=resorcinol–formaldehyde, GO=graphene oxide) obtained from a template‐free self‐assembly synthesis followed by direct calcination. The synthetic process requires no physical mixing step. The phase transformation pathway from tavorite LiFePO₄OH to olivine LiFePO₄ upon calcination was determined by means of the in situ high‐temperature XRD technique. Benefitting from the unique structure of the material, these microspheres can be densely packed together, giving a high tap density of 1.3 g cm⁻³, and simultaneously, defectless LiFePO₄ primary nanocrystals modified with a highly conductive surface carbon layer and ultrathin rGO provide good electronic and ionic kinetics for fast electron/Li⁺ ion transport.

中文翻译：

---

高性能锂离子电池的反位无缺陷纳米LiFePO4 @ C /氧化石墨烯微球的自组装

首先使用基于Fe ³⁺的单一无机前体（LiFePO ₄ OH @ RF / GO； RF =间苯二酚-甲醛）合成具有优异电化学活性和高振实密度的LiFePO ₄ @ C /氧化石墨烯（rGO）分级微球（GO =氧化石墨烯），由无模板自组装合成后直接煅烧制得。合成过程不需要物理混合步骤。利用原位高温XRD技术测定了煅烧过程中铁钛矿型LiFePO ₄ OH向橄榄石型LiFePO ₄的相变途径。得益于独特的材料结构，这些微球可以紧密堆积在一起，从而获得1.3 g cm的高振实密度^-3，同时，用高导电性表面碳层和超薄rGO改性的无缺陷LiFePO ₄初级纳米晶体提供了良好的电子和离子动力学，可实现快速的电子/ Li ⁺离子传输。