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将溶胶凝胶法和低温燃烧法相结合，开发了一种溶胶凝胶自燃烧法合成纳米晶技术，并 用此技术合成了ＬａＦｅＯ３。纳米晶。利用ＸＲＤ、ＴＥＭ和ＢＥＴ对合成的纳米晶进行了结构、形貌、大小和 比表面积的测量和表征。并借助于ＴＧ—ＤＴＡ研究了干凝胶的自蔓延特性和析晶过程。结果表明，由 硝酸盐和柠檬酸盐形成的干凝胶，具有自蔓延燃烧的特性，自燃烧的本质是在硝酸氨的参与下，硝酸 根作氧化剂，柠檬酸中的含碳基团为还原剂（燃料），它们之间发生氧化还原反应。干凝胶自燃烧后， 直接在室温下形成 ４０～６０ ｎｍ具有钙钛矿结构的纯相晶态的 ＬａＦｅＯ３纳米晶。
The sol-gel method and the low-temperature combustion method are combined to develop a sol-gel auto-combustion synthesis of nanocrystalline technology, and the synthesis of LaFeO3 by this technique. Nanocrystalline. The structure, morphology, size and specific surface area of the synthesized nanocrystals were measured and characterized by XRD, TEM and BET. TG-DTA was used to study the self-propagating properties and crystallization of xerogel. The results show that the xerogels formed by nitrate and citrate have the characteristics of self-propagating combustion. The nature of self-combustion is that the nitrate is used as oxidant under the participation of ammonia nitrate and the carbonaceous groups in citric acid are reduced Agent (fuel), between them redox reaction. After self-combustion of xerogel, pure LaFeO3 nanocrystals with perovskite structure of 40-60 nm were formed directly at room temperature.