共查询到19条相似文献,搜索用时 46 毫秒
1.
考察了纳米CuO直接沉淀法制备工艺对其脱硫活性和晶粒尺寸的影响,并利用XRD和TEM对脱硫剂的结构进行了表征。结果表明,所制备的纳米CuO为单斜晶系结构。原料浓度过低、沉淀剂用量小均不利于生成小尺度的纳米CuO。但加热条件下,前驱体有分解形成CuO趋势,晶粒尺寸略有增大;当n(OH-)∶n(Cu2+)=2.5∶1,原料浓度0.4mol/L,搅拌温度为25℃,300℃焙烧时获得的纳米CuO脱硫活性最好,其穿透时间可达640min,此时纳米CuO晶粒尺寸为11.8nm,颗粒的分散性较好;纳米CuO的脱硫活性受其晶粒大小的影响,但只有晶粒尺寸相差较大时,两者之间才呈现出明显的相关性。 相似文献
2.
纳米材料的性能不仅取决于物质种类,而且与粒子的结构和形貌有着密切联系,只有实现对纳米材料微结构的有效控制,才有可能进一步将其应用于微电子器件等高科技领域中。本文基于前人在纳米CuO微观结构上的研究成果,总结了各类纳米CuO的形貌特征,对几种制备方法的优势进行了对比,为纳米CuO的深层次应用提供了借鉴意义。 相似文献
3.
4.
采用沉淀转化法制备CuO的前驱体Cu(OH)2,对纳米CuO微晶的不同热分解条件下的样品进行了x射线衍射(XRD)实验研究。结合所获得的晶粒度和XRD微结构参数,发现纳米晶CuO的晶粒组元中存在着晶格畸变;随着温度的升高,纳米CuO晶粒长大且其微结构呈现出明显的变化,其晶格畸变与晶粒度有着比较密切的关系。 相似文献
5.
采用脉冲电沉积技术在金属Cu基板表面电沉积纳米晶Cu薄膜,在空气中采用热氧化法制备出一维金属CuO纳米针材料。实验研究了脉冲电沉积参数(输出脉冲频率f和占空比r)对电沉积纳米晶的微结构和晶粒度的影响,发现一维CuO纳米针的根部直径与电沉积纳米晶Cu的晶粒度完全一致。通过调节脉冲电沉积参数,能控制电沉积纳米晶Cu的晶粒度,进而实现一维CuO纳米针材料的直径可控分布。 相似文献
6.
7.
8.
9.
10.
11.
激光蒸凝法制备氧化铜纳米粒子 总被引:6,自引:0,他引:6
以150W CW CO2激光器为光源,Cu(AC)2·H2O为靶材,采用激光蒸凝法制备出了氧化铜纳米粒子.初步研究了反应参数对纳米粒子性能的影响,并用X射线衍射、电子衍射、透射电镜等技术对纳米粒子的性能进行了表征,同时对纳米粒子的形成机理进行了初步的探讨.实验结果表明;激光功率密度、反应压力、载气种类及流量等工艺参数对产品的粒度、晶型等性能均有影响.在惰性气氛下,产物主要是Cu和Cu2O,粒径为10~30nm;在氧气气氛下,产物主要是Cu、Cu2O和CuO的混合物,粒径为10~50nm. 相似文献
12.
13.
Guy Applerot Jonathan Lellouche Anat Lipovsky Yeshayahu Nitzan Rachel Lubart Aharon Gedanken Ehud Banin 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(21):3326-3337
To date, there is still a lack of definite knowledge regarding the interaction of CuO nanoparticles with bacteria and the possible permeation of the nanoparticles into bacterial cells. This study was aimed at shedding light on the size‐dependent (from the microscale down to the small nanoscale) antibacterial activity of CuO. The potent antibacterial activity of CuO nanoparticles was found to be due to ROS‐generation by the nanoparticles attached to the bacterial cells, which in turn provoked an enhancement of the intracellular oxidative stress. This paradigm was confirmed by several assays such as lipid peroxidation and reporter strains of oxidative stress. Furthermore, electron microscopy indicated that the small nanoparticles of CuO penetrated the cells. Collectively, the results reported herein may reconcile conflicting concepts in the literature concerning the antibacterial mechanism of CuO nanoparticles, as well as highlight the potential for developing sustainable CuO nanoparticles‐based devices for inhibiting bacterial infections. 相似文献
14.
《Advanced Powder Technology》2020,31(4):1391-1401
A facile and eco-friendly way for fabrication of CuO is developed based on an one-step chemical precipitation route without calcination procedure or use of surfactant. The structure features of as-prepared CuO are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and N2 adsorption-desorption experiment. X-ray diffraction analysis shows that CuO with particle size of 13.5–19.2 nm and crystallinity of 67.0–72.9% can be fabricated by the transformation of Cu(OH)2 precursor at bath temperature above 50 °C. By adjusting the oil bath temperature and the content of ammonium hydroxide, we demonstrate a formation mechanism to control CuO to be 2D leaf-like structure with large specific surface area of 33.4 m2/g and pore volume of 0.226 cm3/g, or 3D flower-like ones with specific surface area of 7.45–18.7 m2/g and pore volume of 0.0249–0.0850 cm3/g. The catalytic performances of as-prepared CuO are evaluated by monitoring degradation of methylene blue in the presence of hydrogen peroxide. Almost 100% methylene blue degradation rate can be reached after reaction for 210 min on 3D flower-like CuO synthesized with 10 mL ammonia content in oil bath of 50 °C. The high activity can be correlated with the morphology and pore volume of CuO. The present synthetic strategy is an inexpensive and convenient way suitable for large-scale fabrication of copper oxides, which are potential catalysts for organic compounds degradation. 相似文献
15.
16.
17.
采用水热法制备了铈离子掺杂的氧化铜纳米颗粒(Ce-CuO NPs)。FESEM图像显示掺杂氧化铜为球形和近球形颗粒;XRD图谱表明,当掺杂量低于10%时,图谱中只出现了单斜结构的CuO衍射峰,当掺杂量增加至15%时,形成了CeO2独立相;ICP分析表明,铈元素的掺杂对CuO NPs中铜离子的释放具有促进作用。铈掺杂氧化铜纳米颗粒的抗菌测试结果显示,其对革兰氏阳性菌金黄色葡萄球菌(S.aureus)的抗菌能力,较革兰氏阴性菌大肠杆菌(E.coli)更为显著;其中,5% Ce-CuO NPs在0.05 mg/mL的低浓度下表现出最佳的抗菌效果。Cu^2+与细菌细胞表面的结合在抑制细菌生长的过程中起到重要作用。 相似文献
18.
分别以乙醇、正丙醇、异丙醇、正丁醇、异丁醇、仲丁醇及叔丁醇等七种有机醇作为共沸剂,采用液相沉淀法结合共沸蒸馏处理前驱体成功合成了分散性良好、粒子尺寸分布为10-20nm的纳米CeO2颗粒,运用TG/DTA、FI—IR、XRD、TEM等方法对不同有机醇的共沸蒸馏作用以及产品性能进行了分析和表征,探讨了共沸蒸馏法制备纳米CeO2的机理。结果表明:共沸蒸馏能起到有效脱除前驱体凝胶中的水分,防止其干燥和焙烧过程中的硬团聚形成的作用,其中七种醇中以正丁醇的共沸蒸馏效果最佳,所得纳米CeO2颗粒的粒度、均匀及分散性能最好。 相似文献