(1. 中南大學(xué) 化學(xué)化工學(xué)院 功能材料化學(xué)研究所， 長(zhǎng)沙 410083;
2. 湖南農(nóng)業(yè)大學(xué) 理學(xué)院， 長(zhǎng)沙 410128)
摘 要: 以自制γ-MnO2（SPDM）和電解二氧化錳（EDM）為原料， 采用流變相法合成了尖晶石型鋰錳氧材料。 應(yīng)用XRD， SEM， TG和DSC等手段研究了原材料性質(zhì)和配比等因素對(duì)合成尖晶石型鋰錳氧的結(jié)構(gòu)、粒徑、 比表面積以及充、 放電性能的影響。 結(jié)果表明， 采用流變相法在700～760℃下， 反應(yīng)12h即可得到均相、 無(wú)雜質(zhì)、 錳平均氧化價(jià)態(tài)接近3.5的LixMn2O4正極材料；以SPDM為錳源較EMD為錳源在相同條件下合成的尖晶石材料的首次充、 放電容量更高， 比表面積更大， 粒度更小；當(dāng)原材料中n(Li)/n(Mn)在一定范圍內(nèi)變化時(shí)， 合成的鋰錳氧的晶格常數(shù)隨材料中鋰與錳摩爾比的增大而減小。
關(guān)鍵字: γ-MnO2； 電解二氧化錳； 流變相法； 尖晶石型鋰錳氧
（1. Institute of Functional Materials and Chemistry,
Central South University, Changsha 410083, China;
2. Faculty of Science, Agriculture University of Hunan, Changsha 410002, China）
Abstract:Spinel-typed LixMn2O4 compounds were synthesized by rheologic phase reaction using a mixture of LiNO3 and self-prepared γ-MnO2 or electrolytic MnO2 and LiNO3 as raw materials. The effects of reaction conditions such as manganese dioxides used and the molar ratio of LiNO3 to MnO2 in raw materials, on the structures, specific area, charge/discharge capacities and other properties of products were investigated by XRD, SEM, TG and DSC. The results show that a homogeneous LixMn2O4 synthesized form γ-MnO2 has higher specific area caused by small particle diameter and higher charge/discharge capacities than that prepared from EMD. The lattice parameter decreases with the increase of n(Li)/n(Mn) when n(Li)/n(Mn) varies in the range of 0.50-0.55.
Key words: γ-MnO2; elctrolytic MnO2; rheologic phase reaction; spinel-typed LixMn2O4
