采用溶胶-凝胶法合成了尖晶石型LiMn2O4粉体,借助TG-DTA(热重/差热分析仪)、XRD(X射线衍射)、SEM(扫描电镜)等测试手段,详细讨论了反应溶液的pH值和凝胶的烧结条件(包括烧结温度、烧结时间、升温速率)对产物晶相结构和形貌的影响.结果表明烧结温度对所制备LiMn2O4粉体的晶相结构和形貌具有重要的影响;在适宜的烧结温度(750℃)前提下,pH值、烧结时间和升温速率对产品晶相结构影响甚微,仅对其形貌具有一定影响.适宜的sol-gel制备LiMn2O4粉体的工艺条件为:pH=6.5、烧结温度为750℃、烧结时间为7h、升温速率为5℃/min.
LiMn2O4 powders with spinel structure have been synthesized by sol-gel method.The effects of solution pH value and sintering conditons(including sintering temperature,sintering reaction time and heating rate) on the crystal structure and morphology of the synthesized LiMn2O4 powders are discussed in detail by using TG-DTA,XRD and SEM.The results show that the sintering temperature has important influences on the crystal structure and morphology of the synthesized LiMn2O4 powders.At the feasible sintering temperature(750 ℃),the pH value,sintering reaction time and heating rate have little influence on the crystal structure of the LiMn2O4 powders,however,they have some effects on the morphology of the product.The optimal sol-gel processing conditions for LiMn2O4 powders are suggested as:pH value is 6.5,sintering temperature is 750 ℃,sintering reaction time is 7 h and heating rate is 5 ℃ /min.