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31.
以TiCl4为原料, 采用溶胶水解法合成了金红石型纳米TiO2颗粒, 并以其为载体制备了WC/TiO2纳米复合材料. 采用X射线衍射(XRD)、扫描电子显微镜(SEM)和X射线能谱(EDS)等手段分析了WC/TiO2纳米复合材料的晶相组成和表面形貌. 结果显示样品是由WC, TiO2和W组成, 纳米WC颗粒均匀地包覆在TiO2的表面, 并与TiO2构成了WC/TiO2纳米复合材料. 采用循环伏安法和计时电流法研究了WC/TiO2纳米复合材料对硝基苯的电催化性能. 结果表明, WC/TiO2纳米复合材料对硝基苯的电催化活性和电化学稳定性均优于介孔结构碳化钨(meso-WC)和纳米WC颗粒(part-WC).  相似文献   
32.
氧化锌纳米棒的制备和生长机理研究   总被引:12,自引:0,他引:12  
ZnO nanorods are prepared by different assistants (cetyltrimethylammonium bromide,trisodium citrate and ethylene diamine anhydrous) favored hydrothermal synthesis with Zn(OH)2 colloid as the precursor. The samples are characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that the as-synthesized ZnO nanorods are of uniform size with 25 nm in diameter and 200~300 nm in length. The effects of the different assistants to the morphology, size and mechanism of nano-ZnO are discussed.  相似文献   
33.
水热法合成MOS2/CNT同轴纳米管   总被引:1,自引:0,他引:1  
夏军保  徐铸德  陈卫祥  郑遗凡  杜志强 《化学学报》2004,62(20):2109-2112,F011
采用水热法合成了MoS2/CNT同轴纳米管.对合成的MoS2/CNT同轴纳米管用高分辨透射电镜(HRTEM)、X射线衍射(XRD)和电子能谱(EDS)方法对其进行了鉴定和表征,发现所制备的MoS2/CNT同轴纳米管结构完好,在CNT的外表面包覆了3~4层MoS2管.初步分析了MoS2/CNT的形成机理.  相似文献   
34.
0引言溶剂作为湿化学法合成无机材料的微环境,其物化性质如极性、粘度、硬度等对无机材料的合成均有重大影响[1]。当前大多数的研究工作主要限于水溶液,有关溶剂性质对无机材料合成影响的研究较少。近年来,利用混合溶剂作为调控合成无机材料的有效手段逐渐引起关注[2 ̄6]。在醇  相似文献   
35.
采用十六烷基三甲基溴化铵(CTAB)辅助水热法合成了Ag/C同轴纳米电缆,并用SEM、TEM、XRD和EDS对产物进行了表征。结果表明,产物为长达数十微米,内核直径80~100 nm,壳厚约100 nm的纳米电缆。初步探讨了Ag/C同轴纳米电缆的生长机制。  相似文献   
36.
α-MnO2 and β-MnO2 nanorods were prepared directly by facile hydrothermal process at 150 ℃ and 220 ℃, respectively. The as-prepared α-MnO2 and β-MnO2 nanorods were shown to be phase-pure single crystallites as evidenced by XRD, TEM and SEM results. Further experiments show that the as-prepared α-MnO2 and β-MnO2 nanorods have catalytic effect on the oxidation and decomposition of the methylene blue(MB) dye with H2O2. The catalytic activity of β-MnO2 is much higher than that of α-MnO2.  相似文献   
37.
过渡金属离子置换钛酸(盐)纳米管的合成和表征   总被引:5,自引:0,他引:5  
以掺杂(Mn、Cr、Cu)的锐钛矿相二氧化钛纳米粉体为前驱体, 采用水热法合成了过渡金属离子置换的钛酸(盐)纳米管, 并用扫描电镜(SEM)、透射电镜(TEM)、能谱元素分析(EDX)、粉末X射线衍射(XRD)、 荧光发射光谱(PL)和拉曼光谱(Raman)对产物进行了表征. 结果表明, 过渡金属离子置换的钛酸(盐)纳米管荧光发射强度随金属离子的置换都有不同程度的降低, 一般认为低电子空穴对复合率意味着高光量子效率. 期望置换后的钛酸(盐)纳米管有可能在催化领域得到应用.  相似文献   
38.
Titanium dioxide (TiO2) nanoparticles of rutile phase were synthesized by hydrolysis of TiCl4 at 95 ℃ in aqueous solution. The samples as prepared and calcined at 500 ℃ were characterized by XRD, TG-DTA and TEM. The sample as prepared was of imperfect rutile structure, and its morphology was rod-like with a diameter of 10~20 nm, a length of 20~80 nm and an aspect ratio of 2~4. The structure of the sample calcined at 500 ℃ was a perfect rutile one, and its morphology was rod-like with a diameter of 15~25 nm, a length of 25~105 nm and an aspect ratio of 2~4. These results indicate that calcination temperature has a positive effect on the structure and the size of rutile nanocrystals, and has no effect on the aspect ratio of rutile nanocrystal. A model for the formation mechnism of rutile nanocrystal in aqueous solution under hydrolysis conditions has been proposed.  相似文献   
39.
过渡金属离子置换钛酸纳米管的制备和光催化活性   总被引:4,自引:0,他引:4  
TiO2纳米粉体和纳米膜材料在光催化降解大气和水中的污染物等方面具有广泛的应用[1]。近年来,以TiO2为原料与浓N aO H反应合成的钛酸纳米管具有比其原料TiO2更大的表面积和孔体积,且对丙烯有光催化氧化降解活性而备受关注[2]。以往在对TiO2纳米粉体和纳米膜材料在光催化研究中,人们发现由于光激发产生的电子与空穴的复合,导致光量子效率很低。为克服这个缺点,人们使用过渡金属离子掺杂等多种手段对TiO2进行改性[3]。但钛酸纳米管相类似的研究还未见报道。对钛酸纳米管的结构和组成的研究表明[4],此纳米管状物的组成是N axH2-xTi3O7,…  相似文献   
40.
BiIO_4 nanoflakes were successfully prepared through a facile hydrothermal method. The as-prepared BiIO_4 was characterized by scanning electron microscope(SEM), high-resolution transmission electron microscopy(HRTEM), X-ray diffraction(XRD), energy-dispersive spectroscopy(EDS) and ultraviolet visible diffuse reflectance spectroscopy. BiIO_4 nanoflakes showed excellent photocatalytic activity for the degradation of phenol solution under simulated solar irradiation. The influence of synthesis temperature on the morphology, size and photocatalytic performance of BiIO_4 was investigated. BiIO_4 prepared under 140 ℃ exhibited the highest removal rate of phenol under simulated solar light irradiation. In addition, the parametric studies such as the effect of catalyst loading and phenol solution pH were carried out to optimize the reaction conditions. The active species trapping experiment demonstrated that h~+ and ·OH are the major active species during the photocatalytic process.  相似文献   
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