Effect of acidity coefficient on the phase composition and morphology of MoO3 synthesized by hydrothermal method
-
摘要: 为研究合成氧化钼的组织结构与控制条件的关系，以仲钼酸铵为钼源，在没有添加任何结构导向剂的情况下，通过简单的水热法制备了六方相三氧化钼（h-MoO3）微米棒和正交相三氧化钼（α-MoO3）纳米带。利用X射线衍射仪、扫描电镜和综合热分析对合成MoO3的物相和形貌进行了表征，研究了酸度系数与MoO3相变过程和形貌变化的关系，分析了相变机理。结果表明，控制水热合成的酸度系数可得到不同相结构和形貌的MoO3。酸度系数小于12.0时，得到h-MoO3；酸度系数超过12.0后，h-MoO3逐渐减少；酸度系数达到48.0时，h-MoO3完全消失，得到α-MoO3纯相。酸度系数超过48.0后，α-MoO3形貌从针状向带状转变，沿着c轴生长，长度不断增加，从而获得一维纳米材料。Abstract: To study the relationship between the structure and the control conditions of molybdenum oxide synthesis, the hexagonal molybdenum trioxide (h-MoO3) microbars and the orthogonal molybdenum trioxide (α-MoO3) nanobelts were prepared by simple hydrothermal method using ammonium paramolybdate as the molybdenum source without any structure guide agent. The phase composition and morphology of the synthesized MoO3 were characterized by X-ray diffraction, scanning electron microscope, and the comprehensive thermal analysis. The relationship between the acidity coefficient and the MoO3 phase transformation and morphology change was studied, and the phase transformation mechanism was discussed. The results show that MoO3 with the different phase structures and morphologies can be obtained by controlling the acidity coefficient during the hydrothermal synthesis. h-MoO3 is obtained when the acidity coefficient is less than 12.0, and gradually converts to α-MoO3 in case that the acidity coefficient is more than 12.0; h-MoO3 gradually decreases, and when the acidity coefficient is 48.0, h-MoO3 completely disappears and α-MoO3 is obtained. After the acidity coefficient is more than 48.0, the morphology of α-MoO3 changes from microbar to nanobelt, which grows along the c axis with the increasing aspect ratio, thus obtaining the one-dimensional nanomaterials.
-
Key words:
- molybdenum trioxide /
- hydrothermal method /
- acidity coefficient /
- microbar /
- nanobelt
-
图 2 低酸度系数产物扫描电子显微形貌：（a）酸度系数2.0；（b）酸度系数3.6；（c）酸度系数6.0
Figure 2. SEM images of the low acidity coefficient products: (a) acidity coefficient 2.0; (b) acidity coefficient 3.6; (c) acidity coefficient 6.0
图 3 仲钼酸铵和酸度系数为2.0、3.6时产物的热重−示差扫描量热曲线:（a）仲钼酸铵；（b）酸度系数2.0；（c）酸度系数3.6
Figure 3. TGA−DSC curves of AHM and products at the acidity coefficient of 2.0 and 3.6: (a) AHM; (b) acidity coefficient 2.0; (c) acidity coefficient 3.6
图 5 中酸度系数产物的扫描电子显微形貌：（a）酸度系数9.0；（b）酸度系数12.0；（c）酸度系数15.0；（d）酸度系数30.0
Figure 5. SEM images of the middle acidity coefficient products: (a) acidity coefficient 9.0; (b) acidity coefficient 12.0; (c) acidity coefficient 15.0; (d) acidity coefficient 30.0
图 7 高酸度系数产物的扫描电子显微形貌：（a）酸度系数30.0；（b）酸度系数48.0；（c）酸度系数73.0；（d）酸度系数91.0
Figure 7. SEM images of the high acidity coefficient products: (a) acidity coefficient 30.0; (b) acidity coefficient 48.0; (c) acidity coefficient 73.0; (d) acidity coefficient 91.0
图 8 酸度系数48.0产物的热重−示差扫描量热曲线
Figure 8. TGA−DSC curves of the products at the acidity coefficient of 48.0
图 9 MoO3结构示意图：（a）α-MoO3；（b）h-MoO3
Figure 9. Structural diagram of MoO3: (a) α-MoO3; (b) h-MoO3
表 1 实验配比和酸度系数
Table 1. Experimental ratio and the acidity coefficient
编号 仲钼酸铵 / g HNO3 / mL 酸度系数 1 6.00 3.2 2.0 2 3.25 3.2 3.6 3 2.00 3.2 6.0 4 1.30 3.2 9.0 5 1.00 3.2 12.0 6 1.00 4.0 15.0 7 1.00 8.0 30.0 8 1.00 13.0 48.0 9 1.00 4.0（浓） 73.0 10 1.00 5.0（浓） 91.0 注：最后两组实验采用的是稀释前的浓硝酸。 
下载: 导出CSV
-
[1] Dong G X, Lü Y N, Han W D, et al The progress of research on electrode materials of super-capacitorsPowder Metall Technol2016 34 5 384 董桂霞, 吕易楠, 韩伟丹, 等 超级电容器电极材料的研究进展粉末冶金技术2016 34 5 384 [2] Lin L, Lü C, Li H Preparation of α-MoO3 nanorods and their NOx gas sensing performanceNew Chem Mater2019 47 6 117 林珑, 吕程, 李海 . α-MoO3纳米棒的制备及其NOx气敏研究. 化工新型材料2019 47 6 117 [3] Yang S L, Li S, Xu H X, et al First-principles study of the humidity sensing property for orthorhombic MoO3J Wuhan Univ Nat Sci2019 65 1 37 杨树林, 李珊, 徐火希, 等 正交相三氧化钼湿度敏感性能的第一性原理研究武汉大学学报(理学版)2019 65 1 37 [4] Xu Z S, Jia H Y, Yan L, et al Combined application effects of MoO3 and OMMT on the flammability of the intumescent flame-retarded epoxy resinsJ Saf Environ2019 19 3 847 徐志胜, 贾宏煜, 颜龙, 等 三氧化钼与有机蒙脱土复配体系在膨胀阻燃环氧树脂中的应用安全与环境学报2019 19 3 847 [5] Wang L C, Gao L, Wang J, et al MoO3 nanobelts for high-performance asymmetric supercapacitorJ Mater Sci2019 54 21 13685 [6] Wu H R, Lian K The development of pseudocapacitive molybdenum oxynitride electrodes for supercapacitorsECS Trans2013 58 25 118 [7] Li C X, Qiu D L, Chen D, et al . Preparation of MoO3−x as high-performance anode material for lithium-ion battery and study on its property. Mod Chem Ind2019 39 12 76 李春晓, 丘德立, 陈东, 等 . 高性能锂离子电池负极材料MoO3−x的制备与性能研究. 现代化工2019 39 12 76 [8] Brezesinski T, Wang J, Tolbert S H, et al Ordered mesoporous alpha-MoO3 with iso-oriented nanocrystalline walls for thin-film pseudocapacitorsNat Mater2010 9 2 146 [9] Li X Y. Molybdenum Oxide-Based Composites Prepared through PEG Induction and Their Electrochemical Properties for Lithium-ion Batteries [Dissertation]. Beijing: University of Chinese Academy of Sciences, 2018李晓艳. PEG诱导下钼氧化物基复合材料的制备及其电化学性能研究[学位论文]. 北京: 中国科学院大学, 2018 [10] Gong F F, Li J W, Wei S Z, et al Study on phase transition of molybdenum trioxide and its electrochemical performanceRare Met Cement Carb2013 41 3 24 宫方方, 李继文, 魏世忠, 等 三氧化钼相变及其电化学性能研究稀有金属与硬质合金2013 41 3 24 [11] Gong F F, Li J W, Wei S Z, et al Hydrothermal synthesis and electrochemical performance of h-MoO3Powder Metall Ind2013 23 1 18 宫方方, 李继文, 魏世忠, 等 水热合成法制备六方相三氧化钼(h-MoO3)及其电化学性能粉末冶金工业2013 23 1 18 [12] Zhang W S, Zhang W X, Zhong S X, et al Chemical precipitation preparation and electrochemical properties of h-MoO3 and α-MoO3J Inner Mongolia Normal Univ Nat Sci2013 42 4 413 张万松, 张文欣, 钟寿仙, 等 化学沉淀法制备六方相、正交相三氧化钼及其电化学性能内蒙古师范大学学报(自然科学汉文版)2013 42 4 413 [13] Song J M, Mei X F, Wang H, et al Synthesis via a HNO3 assisted and photocatalytic property of hexagonal molybdenum trioxideChina Molybd Ind2011 35 5 23 宋继梅, 梅雪峰, 王红, 等 硝酸辅助的六方相MoO3的制备及其光催化性质中国钼业2011 35 5 23 [14] Chithambararaj A, Yogamalar N R, Bose A C Hydrothermally synthesized h-MoO3 and α-MoO3 nanocrystals: new findings on crystal-structure-dependent charge transportCryst Growth Des2016 16 4 1984 [15] Song Y F, Lan X Z, Zhou J, et al Influence of surfactants on morphology of nanoparticles molybdenum trioxideChin J Rare Met2010 34 5 781 宋英方, 兰新哲, 周军, 等 表面活性剂对纳米三氧化钼形貌的影响稀有金属2010 34 5 781 [16] Maheswari N, Muralidharan G Controlled synthesis of nanostructured molybdenum oxide electrodes for high performance supercapacitor devicesAppl Surf Sci2017 416 461 [17] Li J W, Wei S Z, Zhang G S, et al Nano MoO3 phase structural evolution during hydrothermal synthesis and its electrochemical propertiesInt J Electrochem Sci2017 12 2429 [18] Bai S L, Chen S, Chen L Y, et al Ultrasonic synthesis of MoO3 nanorods and their gas sensing propertiesSens. Actuators B2012 174 51 [19] Dhage S R, Hassa M S, Yang O B. et al Low temperature fabrication of hexagon shaped h-MoO3 nanorods and its phase transformationMater Chem Phys2009 114 511 [20] Liu Y L, Yang S, Lu Y, et al Hydrothermal synthesis of h-MoO3 microrods and their gas sensing properties to ethanolAppl Surf Sci2015 359 114 [21] Kumar V, Wang X, Lee P S Formation of hexagonal-molybdenum trioxide (h-MoO3) nanostructures and their pseudocapacitive behaviorNanoscale2015 7 27 11777 [22] Chithambarataj A, Sanjini N S, Bose A C, et al Flower-like hierarchical h-MoO3: new findings of efficient visible light driven nano photocatalyst for methylene blue degradationCatal Sci Technol2013 3 5 1405 [23] Gao B, Zhang X J Hydrothermal synthesis of single crystal α-MoO3 nanobelts and their formation mechanismMater Rev2017 31 1 112 高宾, 张晓军 水热法合成MoO3单晶纳米带及其形成机理材料导报2017 31 1 112 [24] Hu X L, Zhang W, Liu X X, et al Nanostructured Mo-based electrode materials for electrochemical energy storageChem Soc Rev2015 44 2376 [25] Kiran Kumar Reddy R, Kailasa S, Geetha Rani B, et al Hydrothermal approached 1-D molybdenum oxide nanostructures for high-performance supercapacitor applicationSN Appl Sci2019 11 1365 -
点击查看大图
计量
- 文章访问数: 261
- HTML全文浏览量: 132
- PDF下载量: 38
- 被引次数: 0
