不同晶型二氧化锰的可控制备条件研究  

Controllable hydrothermal crystallization of MnO_2 with different crystal forms

作　　者：王歌[1] 赵晓昱[1] 张瑾[1] 邹林[1] 杨立斌[1] 沙作良[1] 

机构地区：[1]天津科技大学化工与材料学院天津市海洋资源与化学重点实验室,天津300457

出　　处：《无机盐工业》2017年第8期16-20,共5页Inorganic Chemicals Industry

基　　金：青海省科技支撑计划(2015-GX-109A);天津科技大学青年创新基金(2015LG09);天津市海洋资源与化学重点实验室开放基金(201503);教育部科研创新团队培育计划([2013]373)

摘　　要：实验以MnSO_4·H_2O-KMnO_4为体系,通过水热结晶制备多晶型的二氧化锰,考察了前驱物比、反应温度、pH、时间以及掺杂阳离子对二氧化锰晶型的影响。最终,实验分别确定了制备α-MnO_2、β-MnO_2、δ-MnO_2的方案:1)n(MnSO_4·H_2O)∶n(KMnO_4)=1∶1,水热反应温度为100℃,反应时间为5 h,pH为中性;2)n(MnSO_4·H_2O)∶n(KMnO_4)=3∶2,水热反应温度为180℃,反应时间为5 h,pH为中性;3)n(MnSO_4·H_2O)∶n(KMnO_4)=3∶8,水热反应温度为100℃,反应时间为3 h,pH为中性。研究表明,前驱物比和反应温度是影响二氧化锰晶型的关键因素,反应时间和pH主要影响结晶完整度,阳离子(K^+、NH_4^+)的存在有利于α-MnO_2的结晶。Polymorphs of MnO2 were prepared by hydrothermal crystallization process in the MnSO4·H2O-KMnO4 aqueous solution system.The influences of precursor ratio,reaction temperature,pH,reaction time,and doping of cations on the crystal forms of MnO2 were investigated.Conclusively,the optimal reaction conditions for growing polymorphs of α-,β-,δ-Mn O2 were determined,respectively：1）n（MnSO4·H2O）∶n（KMnO4）=1∶1,hydrothemal temperature was 100 ℃,hydrothemal reaction time was 5 h,and neutral pH solution;2）n（MnSO4·H2O）∶n（KMn O4）=3∶2,hydrothermal temperature was 180 ℃,hydrothemal reaction time was 5 h,and neutral pH solution;3）n（MnSO4·H2O） ∶n（KMn O4） =3 ∶8,hydrothermal temperature was100 ℃,hydrothermal reaction time was 3 h,and neutral pH solution.As a result,the crystal form could be controlled easily by optimizing the precursor ratio and reaction temperature.Moreover,the reaction time and pH had influence on crystallinity.Additively,K-＋ and NH4-＋ were advantageous to form α-MnO2.

关 键 词：水热结晶 二氧化锰 晶型 

分 类 号：TQ137.12[化学工程—无机化工]