纳米ZrO2的合成对负载Ni催化剂的CH4/CO2重整反应的影响

采用共沉淀法、醇热合成法和干法分别合成了纳米ZrO2（ZrO2 CP、ZrO2 ET和ZrO2 S），用XRD、 BET、SEM等对其结构和表面性质进行表征，以CH4/CO2重整为探针反应研究了不同方法合成的纳米ZrO2负载Ni催化剂的催化性能，并与载体的物化性质进行了关联。实验结果表明，以干法合成的纳米介孔ZrO2 S具有较大的比表面积（133m2/g）和较好的孔径分布(4.9nm)，Ni/ZrO2 S催化剂在CH4/CO2重整反应中表现出较好的催化性能。     

Template Synthesis and Adsorption of Hollow Zr02 Microspheres

以油菜花粉为生物模板,通过温和易控的水浴-陈化法制备了纳/微米结构ZrO2中空微球.利用扫描电子显微镜（SEM）、红外光谱（FTIR）、X射线能谱（EDS）、X射线衍射（XRD）、比表面孔隙度分析、热分析等对所制备的产物和前驱体进行了表征,并对产物的吸附性能进行了初步的研究.结果表明,ZrO2中空微球的球壳由纳米粒子构筑并形成介孔结构.花粉模板前处理方式不同,其模板作用不同,可以获得两种不同球壳厚度、表面形貌和比表面积的ZrO2中空微球.其中＂镂空＂结构的ZrO2微球对铬黑T有良好的吸附性能.对ZrO2中空结构形成的机理进行了分析和讨论.     

稀土离子(Gd3+,Eu3+)加载于纳米介孔ZrO2中的发光

水热合成法制备的高度有序多孔ZrO2具有规则六角排列，均匀纳米孔洞（约1．8nm)，丰富的表面，界面态及比表面积和强的蓝－（近）紫外光发射，使其较常规体材料有更优异的性质，以稀土离子为探针，研究了Gd^3 ,Eu^3 在这些纳米微孔中的发光行为，结果表明，500摄氏度下，介孔ZrO2与稀土离子相作用并有效地将能量传递给稀土离子，增进稀土离子发光，而在ZrO2:Gd-Eu体系中，Gd^3 在ZrO2与Eu3 间起桥梁作用，使基质ZrO2→Eu^3 的能量传递更为有效。     

大孔SO42-/ZrO2-SiO2复合固体酸制备及催化性能

利用浸渍水解法在大孔SiO2载体上组装固体酸制备出大孔径SO42-/ZrO2-SiO2复合固体酸催化剂。用扫描电镜、红外光谱仪和粉末X射线衍射仪等对其进行表征,结果表明:大孔SiO2载体的毛细管效应促使ZrO2以纳米薄层方式均匀地沉积在SiO2薄层表面,并抑制了ZrO2晶体的生长和晶相的转变,载体的大孔全连通的结构赋予该复合材料高的通透性(孔径在1~2μm)、两面活性点和大的比表面积(约156 m2.g-1)。Hammett指示剂法测得经550℃焙烧后产物的酸强度H0值小于-13.75,属于固体超强酸。以乙酸正丁酯的合成为探针反应考察硫酸浸渍液浓度、焙烧温度等制备条件对其催化活性的影响,结果表明,该SO42-/ZrO2-SiO2固体酸具有较好的催化活性,当焙烧温度为550℃和硫酸浸渍液浓度为1.5 mol.L-1时,超强酸对酯化反应的催化酯化率达到97%。     

废轮胎中试回转窑热解炭理化特性及应用前景

采用中试回转窑热解装置对废轮胎进行了热解研究。在450 ℃～650 ℃温度范围内，热解炭的产率约为39%～44%，并具有高灰分（12%以上）和高硫含量特性。热解炭孔容积随热解温度升高而增大，并在550 ℃时达到最大值。在孔径约为50 nm处，热解炭的比孔容积具有最大值。热解炭在CO2和水蒸气气氛下，经活化可得到中等比表面积的活性炭（253 m2/g～306 m2/g），并具有较发达的中、大孔结构。热解炭及其活性炭对亚甲基兰和Pb2+具有良好的吸附性。热解炭作为炭黑使用时，其炭黑特性（结构性等）和硫化胶特性低于高补强N330炭黑。热解炭黑可用作中、低补强性炭黑。     

碱液回流老化ZrO(OH)_2制备纳米晶ZrO_2的影响因素

通过考察回流老化所用的碱液（NH_4OH, NaOH和KOH）介质和容器材质（玻璃 和Teflon）对ZrO(OH)_2凝胶及其焙烧产物ZrO_2的织构／结构和热稳定性的影响， 研究了杂质元素掺杂和凝胶溶解－再沉淀等因素在形成高表面积纳米晶ZrO(OH) _2/ZrO_2过程中的作用。在Teflon容器中，以NH_4OH为介质（pH = 11.5）的回流 老化对ZrO(OH)_2/ZrO_2的性质无明显影响。而使用玻璃容器则可显著提高ZrO(OH) _2/ZrO_2的表面积、孔容和抗烧结性质，并在800℃获得小晶粒（5～7 nm）四方晶 相ZrO_2纳米晶材料；在DTA曲线上ZrO(OH)_2转变成ZrO_2晶体的温度由回流老化前 的463℃提高到810～840℃。在以KOH和NaOH为介质(pH = 13)的实验中，使用玻璃 容器得到与经NH_4OH为介质时相类似的结果；但在Teflon容器中只形成低表面积和 较大尺寸（约20 nm）以单斜相为主的混合晶相ZrO(OH)_2，其在800℃焙烧后形成 大晶粒（35 nm）单斜相ZrO_2。样晶的元素分析结果清楚地揭示出使用玻璃容器时 有SiO_2从器壁溶解掺杂进入ZrO(OH)_2凝胶。样品的表面积和孔容与杂质Si~(4+) 含量之间有顺变关系，表明Si~(4+)掺杂是形成高表面积和大孔容ZrO(OH) _2/ZrO_2、提高ZrO_2晶化温度以及稳定小晶粒四方晶相ZrO_2的最主要因素。在不 发生Si~(4+)掺杂前提下，K~+和Na~+的存在可促进ZrO(OH)_2形成结晶，但对高温 下ZrO_2织构的稳定性影响不大。此外，ZrO(OH)_2凝胶的溶解－再沉淀和骨架网络 有序化也是回流老化影响ZrO(OH)_2/ZrO_2织构的重要因素。     

水合ZrO_2固载12-磷钨杂多酸催化四氢呋喃开环聚合

采用过量浸渍结合溶剂蒸发将12-磷钨杂多酸（TPA）分散于水合ZrO2干凝胶表面（以TPA质量分数表示的固载量为5～65 wt%）,再经120～500℃空气气氛焙烧得到水合ZrO2固载磷钨杂多酸催化剂.借助等离子体原子发射光谱（ICP-AES）、物理吸附、X射线衍射（XRD）、傅里叶变换红外（FTIR）光谱、吡啶吸附红...     

可纺性锆溶胶的制备与应用 Ⅰ.氧化锆连续纤维的制备

以氯氧化锆为原料,异丙醇为溶剂,双氧水为水解促进剂,乙酰丙酮为配位剂,采用溶胶-凝胶法制备了ZrO2前驱体连续纤维,经800℃热处理后得ZrO2连续纤维。用FT-IR、TGA、元素分析和SEM等分析技术表征了纤维的化学结构和形貌观察,研究了可纺性ZrO2溶胶的制备条件和影响因素。结果表明,当n（氯氧化锆）：n（双氧水）：1：3,反应时间6h,陈化温度15℃时可得纺丝性能良好的锆溶胶,ZrO2前驱体连续纤维的成分是部分经乙酰丙酮配位的ZrO2水合物,热处理后ZrO2纤维的平均直径为15μm左右,纤维体中存在大量纳米级气孔,但没有发现明显裂纹。     

用于CH4/CO2重整反应Ni/ZrO2-Al2O3催化剂的结构和抗积炭性能

在表面活性剂P123作用下,通过无机盐的双水解反应制备了介孔ZrO2-Al2O3复合氧化物.研究发现,所得样品具有较大的比表面积和可调变的孔结构.ZrO2可嵌入到Al2O3骨架中形成固溶体,因而热稳定性增加;与Al2O3相比,适量ZrO2加入使ZrO2-Al2O3的酸密度和酸强度增加.在CH4/CO2干气重整反应中,N...     

Experimental and Theoretical Study of Hydrogen Atom Abstraction from Ethylene by Stoichiometric Zirconium Oxide Clusters

The reactions of cationic zirconium oxide clusters （ZrxOy^＋） with ethylene （C2H4） were investigated by using a time-of-flight mass spectrometer coupled with a laser ablation/supersonic expansion cluster source. Some hydrogen containing products （ZrO2）xH^＋（x=-1-4） were observed after the reaction. The density functional theory calculations indicate that apart from the common oxygen transfer reaction channel, the hydrogen abstraction channel can also occur in （ZrO2）x^＋＋C2H4, which supports that the observed （ZrO2）xH^＋ may be due to （ZrO2）x^＋＋C2H4→（ZrO2）xH^＋＋C2H3. The rate constants of different reaction channels were also calculated by Rice-Rarnsberger-Kassel-Marcus theory.     

稀土添加剂对超细ZrO2织构、结构的影响

Pure zirconia and zirconia containing Y or Ce were prepared by Supercritical Drying Method (SCD) followed by calcination in air at temperature up to 700℃. It was found that the zirconia containing Y or Ce possessed much higher specific surface area and larger pore volume than that of pure zirconia. The BET surface area of 3.4Y2O3-96.6ZrO2 without calcination and that calcined at 700℃ were 376.2 m2﹒g-1 and 80.0 m2﹒g-1 respectively, while the corresponding values of pure zirconia were 248.0 m2 ﹒g-1 and 47.8 m2﹒g-1 respectively. It was postulated that the better textural properties of zirconia containing Y or Ce were resulted from preventing zirconia particles sintering in the presence of Y or Ce additive. All of these samples made by SCD had a well-developed mesoporous texture.     

Synthesis of thermally stable zirconia-based mesoporous materials via a facile post-treatment

A novel method of preparing thermally stable zirconia-based mesoporous materials was developed. The zirconia-based mesoporous materials of 2D-hexagonal structure were prepared using zirconium sulfate as the zirconium precursor and cetyltrimethylammonium (CTMA) as the pore-directing agent with the aid of salt in the synthesis solution to reduce the sulfate content in the final product and significantly improve the crystallographic ordering. Post-treatment of the mesoporous material with NaCl solution and lowering the ramping rate to less than 0.2 degrees C/min during the calcination process, however, were the key steps to hinder the growth of the dense zirconia phase and to retain the ordered mesostructure up to 600 degrees C. It was found that a portion of the surfactant (8.9-17.4 wt %) and sulfate ions (0.5-1.2 wt %) were removed during the post-treatment, which prevented the remaining sulfate groups from being reduced by the hydrogen-rich surfactant during the calcination process as confirmed by sulfur K-edge X-ray absorption near edge structure (XANES) and infrared spectroscopy. The maintenance of sulfur in the sulfate state seemed to be important in stabilizing the mesoporous structure of zirconia materials. The mesoporous zirconia materials after extraction with NaCl solution three times and calcination at 550-600 degrees C had the composition ZrO(2-x)(SO4)x with x = 0.10-0.27. The material possesses high surface area (approximately 200 m2/g), large pore volume (approximately 0.10 cm3/g), and wormlike mesopores. In comparison with the mesoporous zirconia materials stabilized by chemical treatment, the present route was simpler and more environmentally friendly and resulted in mesoporous zirconia materials of better thermal stability.     

合成介孔纳米晶体氧化锆的新方法(英文)

通过一种新颖的方法,即软模板-固液技术(CSSL)合成具有高比表面积的介孔纳米晶体氧化锆.首先,通过软模板法以1-十六烷基-3-甲基咪唑溴(C16mim+Br-)为结构导向剂,硫酸锆为无机前驱物合成了介观相氧化锆杂化物,然后该杂化物与固体硝酸铜无机盐研磨并进行热处理.在600℃焙烧后所得到的氧化锆材料具有蠕虫状介孔结构,且孔壁由尺寸约为2.50nm的四方相氧化锆纳米粒子组成.该材料的比表面积为240.0m2·g-1,孔径为4.10nm.与之对应,使用单一的软模板法在相同的温度焙烧后,所得到的氧化锆材料介孔结构坍塌,比表面积仅为9.5m·2g-1.     

Mesoporous carbon/zirconia composites: a potential route to chemically functionalized electrically-conductive mesoporous materials

Mesoporous nanocomposite materials in which nanoscale zirconia (ZrO(2)) particles are embedded in the carbon skeleton of a templated mesoporous carbon matrix were prepared, and the embedded zirconia sites were used to accomplish chemical functionalization of the interior surfaces of mesopores. These nanocomposite materials offer a unique combination of high porosity (e.g., ～84% void space), electrical conductivity, and surface tailorability. The ZrO(2)/carbon nanocomposites were characterized by thermogravimetric analysis, nitrogen-adsorption porosimetry, helium pychnometry, powder X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Comparison was made with templated mesoporous carbon samples prepared without addition of ZrO(2). Treatment of the nanocomposites with phenylphosphonic acid was undertaken and shown to result in robust binding of the phosphonic acid to the surface of ZrO(2) particles. Incorporation of nanoscale ZrO(2) surfaces in the mesoporous composite skeleton offers unique promise as a means for anchoring organophosphonates inside of pores through formation of robust covalent Zr-O-P bonds.     

超临界条件下合成晶型骨架的介孔氧化锆

采用聚氧乙烯型非离子表面活性剂(PEO)为模板剂,超临界乙醇为介质,在不同条件下(各种PEO,不同pH值和络合剂)合成了类似于MSU的介孔氧化锆.XRD,N₂物理脱吸附曲线,TEM及选区电子衍射证明该介孔氧化锆骨架为四方晶型;改变表面活性剂类型、络合剂及pH可调变介孔氧化锆的BET表面积与孔分布.     

介孔二氧化锆的水热合成和表征

以表面活性剂十二烷基磺酸钠为辅助模板剂,合成了具有较高稳定性的介孔二氧化锆。 采用TG、XRD、FT-IR以及N₂吸附-脱附等测试技术对产物进行了表征。 研究结果表明,以阴离子型表面活性剂为模板合成的二氧化锆前驱体具有层状介孔结构,经过NaOH溶液处理后再经500 ℃煅烧仍能保持其介孔结构,显示了良好的热稳定性。 在表面活性剂脱除后得到双孔分布的孔结构,其孔壁为四方晶相结构。 NaOH对其结构的形成起到了关键作用。     

钯负载介孔氧化锆基复合催化材料的合成与表征

利用表面活性剂辅助模板及适当后处理工艺实现了少量贵金属氧化钯及稀土氧化铈在有序介孔氧化锆孔道中或孔道表面的均匀分散/负载. 借助XRD, TEM, EDS等分析手段进行样品结构表征; 同时针对不同催化体系探讨了丙烯催化氧化以及Heck反应的催化性能. 研究结果表明, 贵金属钯/稀土氧化铈负载的有序介孔氧化锆体系对丙烯氧化具有良好催化活性, 钯直接负载介孔氧化锆的体系具有优异的Heck反应催化选择性及较少的催化剂使用量.     

Anionic surfactant‐aided preparation of high surface area and high thermal stability ceria/zirconia‐mixed oxide from cerium and zirconium glycolates via sol–gel process and its reduction property

This work is focused on the ceria zirconia mixed oxide prepared through a surfactant‐introduced synthesis method. High surface area nanoparticle mesoporous ceria/zirconia‐mixed oxide was successfully synthesized and characterized using various techniques. High surface area mesoporous fluorite‐structured CeO₂? ZrO₂ was obtained from the elimination of surfactants upon calcination. A surface area in excess of 205.6 m²/g was obtained after calcination at 500 °C, and dropped to 75.96 m²/g by heating at 900 °C. Temperature‐programming reduction (TPR) results showed that the lowest reduction temperature was obtained from the sample containing 40% zirconia content. Copyright © 2008 John Wiley & Sons, Ltd.     

钇掺杂介孔氧化锆材料的合成与表征

近年来一种新型纳米结构材料-介孔材料引起越来越广泛的兴趣。作者利用表 面活性剂辅助模板及后处理工艺成功实现了过渡金属钇在有序介孔氧化锆骨架中的 掺杂改性。借助XRD，TEM，EDS和荧光光谱以及紫外-可见吸收等分析手段进行样品 结构及性能表征。研究结果表明，金属钇离子能均匀地掺杂于规则的介孔氧化锆骨 架中。掺杂改性后的介孔氧化锆试样经激发后室温下呈现特殊的荧光（蓝光）发射 现象，并认为这种荧光响应与钇掺杂氧化锆产生氧空位缺陷有关。     

阴离子表面活性剂辅助模板途径合成介孔结构氧化锆纳米晶

利用阴离子表面活性剂十二烷基磺酸钠(SDS)为辅助模板剂, 成功地合成了高稳定性的介孔氧化锆纳米晶, 采用DSC-TG, FT-IR, XRD, TEM, UV-Vis以及N₂吸附-脱附等方法对样品进行了表征. 研究表明, 以阴离子型十二烷基磺酸钠合成的氧化锆经600 ℃煅烧后仍为纯四方相, 氧化锆晶粒平均尺寸约为6.5 nm. 阴离子型表面活性剂与有机锆源形成自组装协同作用, 合成的氧化锆具有蠕虫状介孔结构, 经过500 ℃煅烧后介孔结构仍然保持, 且由于表面活性剂的去除, 比表面积显著提高, 显示了良好的热稳定性. 本实验制备的氧化锆纳米晶较一般方法制备的市售纳米氧化锆有明显紫外吸收边蓝移现象.