纳米CeO2的制备方法研究进展

介绍了近年来纳米CeO2的制备方法的研究进展情况,重点分析对比了沉淀法、溶胶-凝胶法、水热法、微乳液法、喷雾热分解法、喷雾反应法等制备纳米CeO2的优缺点,指出了在今后应重点研究和解决的主要问题.     

纳米二氧化铈的化学制备方法及应用研究

综述了纳米CeO2在紫外线吸收剂、催化剂领域、抛光粉、电化学上的应用。对目前主要用于制备纳米CeO2的化学制备方法如水热法、化学沉淀法、溶胶-凝胶法、喷雾反应法等做了介绍,总结了纳米二氧化铈制备方法的研究进展,分析了其优缺点,并对其制备方法的研究方向进行展望。     

纳米碳酸钙的生产工艺评述

该文对目前工业上生产纳米碳酸钙的方法作了较为系统的叙述。对一步碳化法、两步碳化法、多段喷雾碳化法、超重力旋转填充床碳化法制备纳米碳酸钙材料的方法进行了比较和总结,并重点介绍了超重力技术的原理和优点。     

水/油微乳液技术制备单分散纳米CeO2

在十六烷基三甲基溴化铵 正丁醇/环己烷/水溶液组成的水/油型微乳液体系中,运用微乳液制备纳米粒子的原理,利用改进的两相液液法,测定了水/油微乳液的区域,并制备了纳米CeO2粉体.对制备得到的CeO2粉末的形貌特征、物相结构、成分等用透射电子显微镜、X射线衍射分析、热重-差示扫描量热法和红外光谱测试进行了表征.结果表明:在测定的微乳液区内能制备出颗粒分散性好,粒度分布均匀的纳米CeO2粒子,所得颗粒尺寸为3 nm左右.     

纳米碳酸钙生产工艺及其超重力法优越性

较为系统地叙述了目前工业上生产纳米碳酸钙的方法。对一步碳化法、两步碳化法、多段喷雾碳化法、超重力旋转填充床碳化法制备纳米碳酸钙材料的方法进行了比较和总结，并阐述了超重力技术的基本原理及其优越性。     

纳米CeO2制备方法研究进展

对近年来国内外出现制备纳米CeO2的方法做了一下简单的介绍,重点分析了液相法中的沉淀法、溶胶-凝胶法、水热法、微乳液法的优缺点,指出了今后研究的重点和解决的主要问题。     

溶胶-凝胶法制备纳米CeO_2

以硝酸铈和柠檬酸为原料 ,采用溶胶 凝胶 (sol gel)法制备了纳米CeO2 对反应温度、金属离子与配体的摩尔比、凝胶烘干温度、焙烧温度等制备条件对产物的影响进行了研究。结果表明 ,所得CeO2 粒子为立方晶相系 ,呈球形 ,平均粒径达到纳米级。并初步对该方法进行了改进 ,采用微波加热的方法可以缩短反应时间 ,节约能源     

水热法合成纳米CeO2及其光催化性质研究

用水热法制备了纳米CeO2,通过XRD、TEM、IR等测试手段对产物的物相结构、形貌和纳米尺度进行了表征.XRD分析表明,制得的纳米CeO2粒子为萤石结构且晶型比较完整;TEM表明产物颗粒基本为球形,且分散性较好,还分析了热处理温度对CeO2粒子大小的影响.以罗丹明B的光降解为模型反应,研究了在紫外光照射下的CeO2光催化活性,结果表明水热法制备的CeO2粒子,粒径小,吸光能力强,光催化活性高.     

纳米氧化铈制备技术进展

本文简述了近年来国内外有关纳米CeO2的多种制备技术及其研究进展。基于液相法易于工业化放大的优点,着重介绍了液相法中的多种制备方法及相应的优缺点,并展望了今后的重点研究方向。     

共沉淀法制备CeO_2-ZrO_2纳米固溶体的研究

研究了反应温度、沉淀剂浓度及分散剂等因素对共沉淀法制备CeO2-ZrO2固溶体的影响,并利用TEM、XRD等方法对固溶体进行表征。结果表明:在反应温度为18～25℃,氨水浓度为5～6mol/L,分散剂选用聚丙烯酰胺的工艺条件下可制备出平均粒径为10nm左右,粒度分布均匀的纳米CeO2-ZrO2固溶体。     

Effect of preparation temperature on the formation of Sr2CeO4 phosphor particles in the spray pyrolysis

Sr₂CeO₄ phosphor particles were prepared by spray pyrolysis at various preparation temperatures. The effect of preparation temperatures on the morphology, crystal structure and photoluminescence characteristics of the post-treated Sr₂CeO₄ phosphor particles was studied. Phase pure Sr₂CeO₄ phosphor particles were not produced by spray pyrolysis without post-treatment. The optimum post-treatment temperature to produce the Sr₂CeO₄ phosphor particles with high photoluminescence intensity was 1,000 °C in spray pyrolysis. The spherical morphology of the as-prepared particles obtained at high preparation temperatures above 1,400 °C had maintained after post-treatment at 1,000 ‡C. The relative photoluminescence intensities of the Sr₂CeO₄ phosphor particles varied with the preparation temperatures in the spray pyrolysis. The as-prepared particles obtained by spray pyrolysis at preparation temperatures below 1,400 °C converted into phase pure Sr₂CeO₄ phosphor particles after post-treatment at 1,000 ‡C. The optimum preparation temperature of the as-prepared particles was 1,400 °C to produce the Sr₂CeO₄ phosphor particles with spherical shape and high photoluminescence intensity in the spray pyrolysis.     

喷雾干燥-目标产品的功能化

分析了喷雾干燥技术的应用现状，指出了喷雾干燥技术在功能性产品制备方面的重要作用。以产品质量作为最终的目标函数，对喷雾干燥技术提出了更高的要求，特别是利用喷雾干燥技术制备高品质功能性材料，要求喷雾干燥技术的内涵更丰富，与交叉学科的联系更广泛。介绍了以喷雾干燥技术为平台的微胶囊制备、复合离子制备、超细化离子制备、喷雾热解法等新方法的基本原理以及制备实例。指出了喷雾干燥技术新的研究发展方向。     

不球磨无机粉体发光材料制备技术进展

综述了不球磨无机粉体发光材料制备技术进展,着重总结了稀土掺杂型无机粉体发光材料的制备方法。介绍了溶胶-凝胶法,燃烧合成法,微波合成法,共沉淀法,喷雾热解法,水热合成法,气相反应合成法和微乳液法等制备方法。对比总结了每种合成方法的优缺点,并对其未来发展趋势作了展望。综述国内外研究报告和论文82篇。     

Synthesis and Catalytic Activity of Silver-Coated Perlite in the Reaction of Ozone Decomposition

Samples of Bulgarian perlite mineral deposit (natural alumino-silicate glass) in the Rhodope mountain were coated with Ag particles via a spray pyrolysis method. This method allows uniform distribution of the silver particles on the outer shell surfaces. SEM, XPS, FT-IR, and XRD methods were applied for characterization of the samples. The XRD investigations of the pristine samples revealed the formation of metallic silver and a small quantity of Ag₂O₃ phase. The presence of silver was also confirmed by XPS analysis. It was established that Ag/perlite composite prepared by spray pyrolysis is a promising catalyst for ozone decomposition. The high catalytic activity is preserved during the complete course of the catalytic reaction. After the catalytic activity test some structural and phase changes in the samples were observed. The XRD patterns of the ozonated samples proved the presence of metallic silver, AgO and Ag₂O₃ phases. The FT-IR analyses revealed that some bands, assigned to Si-O-Si stretching modes, were shifted to lower frequencies after the ozone decomposition test. In general, the spray pyrolysis method turned out to be a very suitable technique for preparation of highly active silver-coated perlite catalyst for efficient ozone removal.     

The characteristics of X1 type Y2SiO5:Tb phosphor particles prepared by high temperature spray pyrolysis

The X1 type Y₂SiO₅:Tb phosphor particles with high brightness were prepared by spray pyrolysis from spray solution with NH₄F flux material. The phosphor particles prepared by spray pyrolysis at high preparation temperature had spherical shape, fine size and dense morphology. The mean sizes of the phosphor particles prepared at 900 and 1650 °C were 1.3 and 0.9 μm. The emission spectrum of the phosphor particles prepared by spray pyrolysis at 1650^oC had the characteristics of X1 type Y₂SiO₅:Tb phosphor. The photoluminescence intensity of the phosphor particles directly prepared by spray pyrolysis from spray solution with 20 wt.% NH₄F flux of the product at temperature of 1650 °C was 127 and 184% of the X1 and X2 type Y₂SiO₅:Tb phosphor particles post-treated at 1100 and 1300 °C, respectively. The Y₂SiO₅:Tb phosphor particles prepared by spray pyrolysis at 1650 °C had X1 type crystal structure because of short residence time of particles inside hot wall reactor of 0.4 s.     

氧化物修饰电极及其在电化学处理有机废水中的应用

对比分析了氧化物修饰电极的制备方法,主要包括溅射法、喷雾热解法、涂层热解法、溶胶-凝胶法、电沉积法等。介绍了国内外采用氧化物修饰电极处理含酚、硝基苯、氯酚、染料等难降解有机废水的应用情况,分析了该方法存在的一些问题,并展望了氧化物修饰电极在有机废水处理方面所具有的巨大潜力。     

喷雾热解法制备薄膜技术

介绍了喷雾热解法制备薄膜技术,综述了喷雾热解法制备薄膜的研究进展,着重介绍了喷雾热解法制备铁电薄膜的研究,以及等离子体增强喷雾热解法制备薄膜技术。     

纳米多孔二氧化钛薄膜的制备及其亲水性能的研究

分别采用溶胶-凝胶法,水热合成法,热雾喷解法制备了纳米多孔TiO2薄膜。以X射线衍射,扫描电镜等方法分析了不同制备方法所得薄膜结构与形貌。通过比较不同方法制备的TiO2薄膜的亲水性能,得知溶胶—凝胶法制备的薄膜和玻璃载体结合最紧,而且表面平整。热雾喷解法制备的薄膜具有最大的比表面积,其亲水性能也最好。同时表明,纳米多孔TiO2薄膜在紫外光照射以后,具有比一般薄膜更持久的亲水型。     

喷雾热解法制备高纯超细氧化铝粉

本文以高纯硫酸铝铵为原料，用喷雾热解法制得纯度大于９９．９％、细度为１０￣２０ｎｍ的高纯超细α－Ａｌ２Ｏ３粉。探讨喷雾热解工艺条件对粉体性能的影响。     

A Pulse Combustion-Spray Pyrolysis Process for the Preparation of Nano- and Submicrometer-Sized Oxide Particles

The preparation of nano- and submicrometer particles using an integrated pulse combustion–spray pyrolysis process was investigated for the first time. Zinc oxide nanoparticles with average sizes ranging from 20 to 40 nm were synthesized using a salt precursor with a lower decomposition temperature than the pulse combustion (PC) temperature. Particles of a doped-type oxide, gadolinium oxide-doped with europium, were also produced from a precursor, whose decomposition temperature was higher than the PC temperature, and were observed to be ellipsoidal–toroidal in shape and submicrometer in size. The high-intensity fluctuating pressures generated by PC and the precursor decomposition temperature are proposed as the reasons for the formation of either nanoparticles or aspherical particles. In addition, hot gas fluctuating flow in PC enhanced energy transfer, resulting in more crystalline particles, as compared with particles produced by conventional spray pyrolysis.