| 不同W氧化度钠钨青铜的结构特征与合成方法探究 |
| |
| 引用本文： | 李灵慧,李艳,黎晏彰,鲁安怀,丁竑瑞.不同W氧化度钠钨青铜的结构特征与合成方法探究[J].岩石矿物学杂志,2020,39(2):195-202. |
| |
| 作者姓名： | 李灵慧 李艳 黎晏彰 鲁安怀 丁竑瑞 |
| |
| 作者单位： | 北京大学 造山带与地壳演化教育部重点实验室, 环境矿物功能北京市重点实验室, 北京 100871,北京大学 造山带与地壳演化教育部重点实验室, 环境矿物功能北京市重点实验室, 北京 100871,北京大学 造山带与地壳演化教育部重点实验室, 环境矿物功能北京市重点实验室, 北京 100871,北京大学 造山带与地壳演化教育部重点实验室, 环境矿物功能北京市重点实验室, 北京 100871,北京大学 造山带与地壳演化教育部重点实验室, 环境矿物功能北京市重点实验室, 北京 100871 |
| |
| 基金项目： | 国家自然科学基金（41522201，41820104003，91851208） |
| |
| 摘 要： | 钠钨青铜NaxWO3(0≤x≤1)因其特殊的物理化学性质受到学者的日益关注,它是一种孔道结构的非严格计量含钨化合物,Na+填充于由WO6]八面体排列组合起来的二级结构空隙中。随着x值的增加,W的平均氧化度逐渐降低,NaxWO3依次发生单斜-正交-四方Ⅰ(空间群I4/nmm)-六方-四方Ⅱ(空间群P4/mbm)-立方晶体结构的转变,结构对称型逐渐升高(四方Ⅱ型除外)。本文从晶体化学角度系统研究了不同W平均氧化度钠钨青铜的结构特征,并通过固相合成法得到了四方和立方钠钨青铜,通过水热合成法得到了六方钠钨青铜。实验结果表明,在固相合成过程中,还原剂NaBH4的量越多,W还原的价态越低,实现钠钨青铜NaxWO3由四方结构向立方结构的转变;在相同还原剂量情况下,合成温度越高,得到的钠钨青铜结构对称型越高;合成立方钠钨青铜的温度一般为700~850℃,高于四方钠钨青铜的合成温度(600~700℃);反应需要适当的酸碱度环境,合成四方和六方钠钨青铜的pH值应控制在6左右,在水热合成过程中,六方结构的钠钨青铜pH值设在2附近较适宜。本文为钠钨青铜系列化合物及不同结构钠钨青铜的合成提供了参考。
|
| 关 键 词： | 钠钨青铜 晶体结构 W氧化度 钨氧八面体 |
| 收稿时间： | 2019/9/7 0:00:00 |
| 修稿时间： | 2019/11/26 0:00:00 |
Structure characteristics and crystal synthesis of sodium tungsten bronze with different W structure oxidation degrees |
| |
| LI Ling-hui,LI Yan,LI Yan-zhang,LU An-huai and DING Hong-rui.Structure characteristics and crystal synthesis of sodium tungsten bronze with different W structure oxidation degrees[J].Acta Petrologica Et Mineralogica,2020,39(2):195-202. |
| |
| Authors: | LI Ling-hui LI Yan LI Yan-zhang LU An-huai and DING Hong-rui |
| |
| Institution: | Key Laboratory of Orogenic Belts and Crustal Evolution, Beijing Key Laboratory of Mineral Environmental Function, School of Earth and Space Sciences, Peking University, Beijing 100871, China,Key Laboratory of Orogenic Belts and Crustal Evolution, Beijing Key Laboratory of Mineral Environmental Function, School of Earth and Space Sciences, Peking University, Beijing 100871, China,Key Laboratory of Orogenic Belts and Crustal Evolution, Beijing Key Laboratory of Mineral Environmental Function, School of Earth and Space Sciences, Peking University, Beijing 100871, China,Key Laboratory of Orogenic Belts and Crustal Evolution, Beijing Key Laboratory of Mineral Environmental Function, School of Earth and Space Sciences, Peking University, Beijing 100871, China and Key Laboratory of Orogenic Belts and Crustal Evolution, Beijing Key Laboratory of Mineral Environmental Function, School of Earth and Space Sciences, Peking University, Beijing 100871, China |
| |
| Abstract: | NaxWO3(0≤x≤1)has received increasing attention from experts due to its special physicochemical properties.It is a non-stoichiometric W-containing compound with the tunnel structure,and Na+filled in the secondary structural tunnels produced by the connection ofWO6]octahedron.With the increase of x,the average oxidation degree of W decreases gradually,NaxWO3 undergoes monoclinic-orthogonal-tetragonalⅠ(space group I4/nmm)-hexagonal-tetragonalⅡ(space group P4/mbm)-cubic crystal structure transformation.Structural symmetry gradually increases except for the tetragonalⅡtype.In this paper,the structural characteristics of sodium tungsten bronze with di-fferent W oxidation degrees were systematically studied from the perspective of crystal chemistry.The tetragonal and cubic phase sodium tungsten bronze was obtained by solid phase synthesis,and the hexagonal tungsten bronze was obtained by hydrothermal synthesis.Experimental results show that,in the solid phase synthesis process,the more the reducing agent NaBH4,the more the reduction of W to a lower valence state,and the easier the conversion of the NaxWO3 from the tetragonal to cubic structure.At the same reduction dose,the higher the synthesis temperature,the higher the symmetry of the obtained sodium tungsten bronze.The temperature of synthetic cubic sodium tungsten bronze is 700~850℃,which is higher than the synthesis temperature of tetragonal sodium tungsten bronze(600~700℃);the synthesis reaction requires appropriate pH value,the p H value is controlled at around 6 when tetragonal and cubic sodium tungsten is synthesized,and the p H value of the hydrothermally synthesized hexagonal sodium tungsten bronze is preferably around 2.The result obtained by the authors provides a reference for sodium tungsten bronze series compounds and the synthesis of different structures of sodium tungsten bronze. |
| |
| Keywords: | sodium tungsten bronzes crystal structures W oxidation degree tungsten-oxygen octahedron |
| 本文献已被 CNKI 维普 等数据库收录！ |
| 点击此处可从《岩石矿物学杂志》浏览原始摘要信息 |
| 点击此处可从《岩石矿物学杂志》下载免费的PDF全文 |
|
