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1.
通过乳液界面反应法, 利用以Span80(sorbitan monooleate)作为稳定剂的乳液体系控制合成了叶状Cu(OH)2单晶. 通过热处理, 可以得到表面有纳米孔的CuO, 且保持了原有的叶状形貌. 通过X射线衍射(XRD)、Fourier红外光谱(FTIR)、扫描电镜(SEM)和透射电镜(TEM)观测了其形貌和结构特征. 实验结果表明, 叶状Cu(OH)2为单晶, 且沿[111]晶面定向生长. 孔的形成是由于相转变过程中Cu(OH)2失去H2O分子所致. 通过观测不同反应时间产物的形貌, 深入探讨了叶状Cu(OH)2纳米结构的组装机理. 整个组装过程是由能量高的颗粒状纳米粒子通过端部取向连接定向生长而得到能量相对较低的叶状结构. 并且得到的CuO的紫外光谱相对于其块体材料发生了蓝移, 显示出比较大的禁带宽度.  相似文献   

2.
以CuSO4.5H2O和NaOH为原料,采用沉淀法制备得到Cu(OH)2纤维,再进行Cu(OH)2的分解反应.考察了在不同实验条件下温度对Cu(OH)2热分解过程的影响.结果表明:在反应温度20℃,反应终点pH值为12,搅拌速度为1 200 r.min-1,NaOH溶液的滴加速度为50 mL.min-1的反应条件下,得到的样品为纳米Cu(OH)2纤维,其直径为10~30 nm、长度为1~6μm;在固相纳米Cu(OH)2热分解制备CuO过程中CuO粒径随温度的升高而增大,在温度不超过200℃时CuO的粒径约为20 nm左右;在液相中先沉淀后升温时,产物的形貌为球形,CuO粒径随温度的升高而增大,低于80℃可得到纳米级的CuO.  相似文献   

3.
彭银  刘正银  叶峰  魏先文 《中国化学》2009,27(2):295-298
聚丙烯酰胺(PAM)表面活性剂的作用下,在温和的低温水溶液中,合成了Cd(OH)2油炸圈饼状微米结构。这种结构是由单晶结构的六方片状Cd(OH)2按一定排列方式自组装而成。在羰基修饰的PAM(PAM-COOH)表面活性剂作用下,得到中心有孔的油炸圈饼纳米结构。可能的生长机理为表面活性剂控制下Cd(OH)2纳米片经历有序连接过程,最终形成油炸圈饼状结构。聚合物诱引晶体生长与调控纳米晶自组装将提供了一条有效的路径来合成具有复杂形貌与特殊结构的无机和无机-有机杂化材料。  相似文献   

4.
分别以过硫酸钾、 过硫酸铵及氨水为氧化剂, 在铜表面制得纳米结构, 并用十七氟癸基三乙氧基硅烷(FAS-17)进一步氟化处理, 获得了差异化超疏水表面. 比较了不同氧化剂对反应结果的影响, 并分析了氧化反应的历程. 实验结果表明, Cu首先被O2氧化成CuO超薄层, 然后水解变成Cu(OH)2, 并进一步被OH-或NH4OH络合成蓝色溶液. 不同形貌纳米结构是Cu(OH)2在饱和析出过程中沿固定晶面堆砌的结果. 最后对不同纳米结构超疏水表面的耐水蒸气冷凝情况及微观机理进行了分析, 证实只有较密、 较垂直的纳米针结构表面才耐水蒸气冷凝, 即冷凝水滴在其上出现快速自迁移现象.  相似文献   

5.
三种新型铜配合物的合成、结构及理论计算   总被引:1,自引:0,他引:1  
合成了一个柔性配体1,3-二(N-咪唑基甲基)苯(mbix)(1), 并将其与不同Cu盐组装, 得到3个新配合物[Cu(mbix)2(H2O)]·2NO3·CH3OH(2), [Cu(mbix)(N3)(OAc)]·CH3OH(3)和[Cu(mbix)2]·SiF6·2CH3OH(4), 并对其进行了元素分析、红外光谱及X 射线单晶结构分析表征. 配合物2拥有二维二重贯穿结构, 配合物3中两个铜离子通过两个叠氮酸根桥连成双核铜, 它再通过配体连接形成一维绞链状结构, 而配合物4通过配体桥联成一维无限链状结构. 结果显示, 平衡阴离子在配合物的组装过程中起着非常重要的作用. 此外还对配体及3个配合物中配体的构象进行了理论计算.  相似文献   

6.
用配体磺基水杨酸,1,10菲罗啉和CuCO3·Cu(OH)2·H2O反应合成了配合物[Cu3(hssal)2(phen)2(H2O)4]·2CH3OH(1)(H3hssal:磺基水杨酸;phen:1,10菲罗啉),用单晶X-射线衍射、元素分析和红外光谱对该配合物进行了表征。研究了1的固体荧光和热稳定性,并用它作为前驱体合成了CuO微晶粒子,用粉末XRD和SEM对合成的CuO进行了表征和形貌研究。  相似文献   

7.
微波辅助水热法制备花状氧化铜   总被引:2,自引:2,他引:0  
以硝酸铜为铜源,氨水为碱源,通过微波辅助水热法制备了花状CuO微纳米材料。制备过程中没有使用表面活性剂或离子液体等软模板剂。利用X-射线衍射、电子能谱、场发射扫描电镜以及高分辨透射电镜表征了产物的物相和形貌。对照实验显示碱源对产物形貌有着很大的影响。通过时间演化实验研究了花状CuO的生长过程。结果显示反应过程经历了Cu2(OH)3NO3和Cu(OH)2两种中间产物。  相似文献   

8.
通过将传统水滴模板法中的单相成膜液改造为反相乳液体系,引进乳液水滴来加载蛋白质组分,实现了对亲水组分直接实施水滴模板法从而获得其阵列组装结构.利用壳聚糖纳米粒子作为皮克林反相乳液的乳化剂制备了稳定的反相乳液体系,并进一步得到聚乳酸/壳聚糖/牛血清白蛋白的杂化蜂窝状多孔薄膜,考察了壳聚糖粒子对于乳液稳定和所制备多孔阵列结构形貌的影响,研究了加入蛋白质浓度和乳液中的水相/油相比例对于所成膜孔形貌的影响,利用荧光标记蛋白质跟踪确认基于蜂窝状多孔阵列结构上的图案化蛋白质阵列组装形貌.  相似文献   

9.
使用四丁基氢氧化铵-正硅酸四乙酯-水(TBAOH-TEOS-H2O)简单体系一步水热制备了具有多级孔道的微米级MEL结构分子筛聚集体.得到的silicalite-2微米球直径大于10μm且具有高达460 m2·g-1的比表面积和0.74 cm3·g-1的孔体积.微米球的生成一定程度上解决了催化应用过程中催化剂的分离和回收问题.同时,水热晶化过程中由纳米粒子自组装而成的晶间介孔缩短了反应物分子的扩散路径,保持了分子筛纳米晶粒的优势.此外,钛活性位的引入并未明显影响MEL微米球的形貌和结构,含钛的MEL微米球TS(钛硅分子筛)-2在苯酚羟基化反应中具有与纳米尺寸TS-1(100-200 nm)相当的催化活性,且TS-2可以通过简单过滤得到,简化了纳米级TS-1的分离和回收过程.  相似文献   

10.
在制备CuO/ZnO/Al2O3催化剂的老化过程中,采用微波辐射老化技术,着重研究了溶剂极性对前躯体物相组成,烧后CuO/ZnO/Al2O3催化剂结构及其在浆态床合成甲醇工艺中催化性能的影响。通过XRD、DTG、H2-TPR,FTIR、HR-TEM和XPS对前驱体及催化剂表征表明,沉淀母液在微波辐射条件下进行老化,溶剂的极性对前躯体物相组成及催化剂结构影响显著。随着溶剂极性的增大,Zn2+/Cu2+取代Cu2(CO3)(OH)2/Zn5(CO3)2(OH)6中Cu2+/Zn2+的取代反应增强,使得前躯体中(Cu,Zn)5(CO3)2(OH)6和(Cu,Zn)2(CO3)(OH)2物相的含量增多,结晶度提高,导致烧后CuO/ZnO/Al2O3催化剂中CuO-ZnO协同作用增强,且CuO晶粒减小,表面Cu含量增加,催化剂活性和稳定性提高。水溶剂的极性最大,制备的催化剂活性和稳定性最好,甲醇的时空收率(STY)和平均失活率分别为320 mg.g-1.h-1和0.11%.d-1。  相似文献   

11.
Leaf-like Cu(OH)2 single crystals were synthesized via the controlled emulsion interface method using Span80 (sorbitan monooleate) as the stabilizer of the emulsion system. CuO products with nanopores could be simply obtained by the dehydration of Cu(OH)2, while maintaining the strip-shaped architecture. The phase structures and morphologies were measured by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectra, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Experimental results showed that Cu(OH)2 microleaves were single crystals and the growth direction seemed to be in [111] crystal plane of the orthorhombic Cu(OH)2. The formation of the nanopores should be attributed to the water loss of the transformation from Cu(OH)2 to CuO. The formation process of Cu(OH)2 was investigated by taking TEM images at different stages of the reaction. The formed nanoparticles began to rearrange to form nanorods and microleaves possibly via edge-by-edge and side-by-side oriented-attachments because of the formation of larger crystals greatly reducing the interfacial energy. Besides, CuO microarchitectures exhibit blue shifts in UV-Vis spectra and possess larger band gaps compared with those of bulk crystals.  相似文献   

12.
Tetrabutylammonium hydroxide/water mixtures are efficient reaction media for the fabrication of nanoscale metal oxides and hydroxides. Uniform CuO nanoplates, among others, can be grown on a large scale. This work shows that after 30 s at temperatures above 40 degrees C, CuO formation is already essentially complete. X-ray diffraction and transmission electron microscopy (TEM) show that the resulting plates form via a two-step process, where Cu(OH) 2 rods precipitate first. These rods aggregate and fuse into plates with a width/height ratio of about 1.9. High-resolution TEM and electron diffraction show that the plates are single crystals and exhibit only some defects, which most likely originate from the assembly and fusion of the primary rods.  相似文献   

13.
In this paper, CuO, CuO/Cu2O, Cu2O, Cu2O/Cu and Cu microcrystals were synthesized via a hydrothermal method by mixing Cu(NO3)2·3H2O and NaOH together in the presence of an ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate([BMIM]BF4) or 1-butyl-3-methylimidazolium chloride([BMIM]Cl). The structures and the morphologies of the obtained products were characterized by means of X-ray diffractometer(XRD), field-emission scanning electron microscopy/energy-dispersive spectroscopy(FESEM/EDS), transmission electron microscopy/selected area electron diffraction(TEM/SAED) and Raman spectroscopy. The result of XRD indicates that Cu2O and Cu microcrystals are cubic phase and the Raman spectra confirm the presence of carbon. The results of FESEM and TEM images show Cu2O microcrystals as rule cubes of 2 μm in length and Cu particles of 5 μm in diameter. According to the difference between crystal structures, bi-component and single component products were synthesized by adjusting the reaction conditions. A possible formation mechanism of Cu2O and Cu was proposed in[BMIM]BF4.  相似文献   

14.
CuO feather‐like and flower‐like crystals have been synthesized by a fast microwave‐assisted solution approach using Cu(NO3)2 and NaOH. The morphology transformation of CuO could be achieved by ionic liquid 1‐n‐butyl‐3‐methyl imidazolium tetrafluoroborate ([BMIM]BF4). With [BMIM]BF4, flower‐like CuO were obtained, whereas without [BMIM]BF4, feather‐like CuO were obtained. The possible formation mechanism of flower‐like CuO was discussed on the basis of experimental results. The products were characterized by XRD, FESEM/EDS, and TEM/SAED. In addition, the adsorption of [BMIM]BF4 on flower‐like CuO was confirmed by FTIR and TG/DSC, and the band gap energies of the flower‐like CuO was estimated by UV‐vis spectra.  相似文献   

15.
Janus Cu2(OH)2CO3/CuS microspheres were prepared via a Pickering emulsion route for the first time. By treating the Janus Cu2(OH)2CO3/CuS microspheres with dilute hydrochloric acid, ringent Cu2(OH)2CO3/CuS core/shell microspheres and ringent CuS shells were obtained. The hatch size of the ringent CuS shells increased with the increase of the hydrophobicity of the precursor Cu2(OH)2CO3 microspheres. Scanning electron microscopy, X-ray diffraction, energy dispersion spectra, and particle size analysis were used to characterize the products thus formed.  相似文献   

16.
Porous copper oxide (CuO) hollow microspheres have been fabricated through a simple hydrothermal method using PS latex as templates. The as-obtained samples were characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR). The influences of the mole ratio of Ethylenediamine (C2H8N2) and copper acetate (Cu(Ac)2·H2O), hydrothermal temperature and time on the size and morphologies of the final products have been investigated. The possible formation mechanism of porous CuO hollow microspheres has been proposed and the specific surface area of the hollow microspheres with 81.71 m2/g is measured by BET method. The band gap value calculated from a UV–vis absorption spectrum of porous CuO hollow microspheres is 2.71 eV. The as-synthesized product exhibits high photocatalytic activity during the photodegradation of an organic dyestuff, rhodamine B (RhB), under UV-light illumination.  相似文献   

17.
β‐Co(OH)2, CuO and ZnO nanostructures with plate‐like, particle‐like and flower‐like morphologies were prepared through the use of simple solvothermal method using of melt salt and 1,10‐phenanthroline as complexing agent and sodium hydroxide. β‐Co(OH)2 consisted of a plate‐like structure, and the nanoplates size was about 29 nm. The structure was comprised of regular sheets which were assembled together. Furthermore, the as‐obtained β‐Co(OH)2 nanoplates can be easily converted into Co3O4 nanoplates by calcining in air at 500 °C for 2 h. The results indicate that ZnO powder is of hexagonal wurtzite structure and well crystallized with high purity. CuO powder is pure monoclinic‐structured crystalline. The products were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FT‐IR) spectra. Possible formation mechanism of the nanostructures is proposed.  相似文献   

18.
以聚乙烯吡咯烷酮(PVP)为高分子模板剂,乙酰丙酮钒(C_(15)H_(21)O_6V)和三水合硝酸铜[Cu(NO_3)_2·3H_2O]为原料,导电玻璃(FTO)为载体,结合溶胶-凝胶法和静电纺丝技术制备了前驱体纤维,经高温焙烧后得到分布均匀、具有纤维结构的导电玻璃负载的CuO/V_2O_5复合光电极(CuO/V_2O_5/FTO).采用热重-差热分析仪(TG-DTA)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线光电子能谱仪(XPS)等对材料的结构进行表征,以亚甲基蓝(MB)为目标降解物,探讨了合成产物的光电催化性能.结果表明,CuO与V_2O_5能有效形成异质结构,其光电催化活性均比纯V_2O_5有明显提高,并且改变CuO与V_2O_5的比例对光电催化性能有较大影响,其中n(Cu)∶n(V)=1∶1时降解效率最高,达到96%.  相似文献   

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