CN101214928B - Method for Synthesizing Ordered Mesoporous Metal Oxide with High Specific Surface Area Using Hard Template - Google Patents

Abstract

A synthesis method of order mesoporous metal oxide with high specific surface area by hard template agent belongs to the filed of the preparation of solid mesoporous materials. The prior art is difficult to control the problems of the hydrolysis rate of metal salt, easy collapse and the poor universality of channels when templates are removed by calcination, etc. In the invention, firstly, hard template agent cubic-phase mesoporous silicon oxide powder is synthetized; the silicon oxide powder is added into 50 to 95wt percent of ethyl alcohol solution of metal salt with the concentration of 0.12 to 0.40 mol/L to form mixed solution; after 90 to 120 min of ultrasonic dispersion, the product is mixed again, vaporized under the temperature of 40 DEG C to 50 DEG C and dried; and then the product is heated to 400 DEG C to 850 DEG C in atmosphere at 1 DEG C/min, and kept for 4 hours under the temperature to obtain the mesoporous oxide precursor powder; the mol ratio of the cubic-phase mesoporous silicon oxide powder and the metal salt is 7-14; 10wt percent of HF solution is used to wash, so as to remove the cubic-phase mesoporous silicon oxide template agent, and the product is dried under 60 DEG C to 70 DEG C for 20 to 24 hours. The mesoporous metal oxide of the invention is suitable to be adsorbent, catalyst, carrier, etc., and is applicable to dyes, magnetic, photoelectric materials, etc.

Description

Translated fromChinese

利用硬模板剂合成高比表面积有序介孔金属氧化物的方法 Method for Synthesizing Ordered Mesoporous Metal Oxide with High Specific Surface Area Using Hard Template

技术领域technical field

本发明涉及一种固体介孔材料制备技术，具体涉及一种利用立方相介孔氧化硅(KIT-6)粉末作为硬模板剂来合成高比表面积有序介孔金属氧化物的方法。 The invention relates to a preparation technology of solid mesoporous materials, in particular to a method for synthesizing ordered mesoporous metal oxides with high specific surface area by using cubic phase mesoporous silicon oxide (KIT-6) powder as a hard template. the

背景技术Background technique

近年来，纳米粒子和有序孔材料制备技术得到了迅速发展，使得可控合成此类材料成为可能。由于介孔氧化物材料不仅具有较高的比表面积和孔容，使其成为表面结构和多相催化等方面的重要研究对象，被广泛地应用于气体分离、多相催化、储能、印染，电磁，光电等众多领域。因此，研发高比表面积的介孔金属氧化物的制备方法具有重大的实用价值。 In recent years, the preparation technology of nanoparticles and ordered porous materials has been developed rapidly, making it possible to controlly synthesize such materials. Due to the high specific surface area and pore volume of mesoporous oxide materials, it has become an important research object in surface structure and heterogeneous catalysis, and is widely used in gas separation, heterogeneous catalysis, energy storage, printing and dyeing, Electromagnetic, optoelectronic and many other fields. Therefore, it is of great practical value to develop a method for preparing mesoporous metal oxides with high specific surface area. the

介孔金属氧化物通常的制备方法是使用软模板剂的溶胶-凝胶法，即利用所要求的无机盐前驱物与软模板剂形成溶胶，在一定温度下活化前驱物，再在一定条件下除去有机软模板剂，最后可得到具有介孔结构的目标产物。例如，Sinha等采用以F127、乙二醇和丙醇为混合模板剂，以硝酸铬为铬源，通过溶胶-凝胶过程，再经400℃灼烧后，合成出比表面积为96m²/g和孔径为7.9nm的介孔氧化铬(A.K.Sinha，et al.，Angew.Chem.Int.Ed.，2005，44：271；A.K.Sinha，et al.，Appl.Catal.B，2007，70：417)。Yan等则利用不同摩尔比的柠檬酸和硝酸铬混合物的固溶胶在封闭条件下，通过热分解方法制得了不同形貌、不同尺寸、不同孔结构的氧化铬(Z.F.Yan，et al.，J.Phys.Chem.B，2006，110：178)。Guzman等利用经氨基酸修饰的氧化钇溶胶，用P123做模板剂制备出比表面积为90m²/g和孔径为6.5nm介孔氧化钇(J.Guzman，et al.，Chem.Commun.，2005，743)，Wang等则在超声辅助下，使用十二烷基硫酸钠做模板剂，硝酸盐做金属源，尿素做沉淀剂制备出孔径分别为4.7nm和4.2nm的介孔结构的氧化钐和氧化铒(Y.Wang，et al.，Ultrasonics Sonochem.，2002，9：285)。然而，上述方法也存在一些局限，难于控制金属盐的水解速率、煅烧去除模板时孔道容易塌陷、方法的普适性差等等。从而大大地限制所得介孔金属氧化物的应用。 The usual preparation method of mesoporous metal oxides is the sol-gel method using soft templates, that is, using the required inorganic salt precursors and soft templates to form a sol, activating the precursors at a certain temperature, and then activating the precursors under certain conditions. After removing the organic soft template, the target product with mesoporous structure can be obtained finally. For example, Sinha et al. used F127, ethylene glycol and propanol as a mixed template, and chromium nitrate as a chromium source, through a sol-gel process, and then burned at 400 ° C to synthesize a specific surface area of 96m² /g and Mesoporous chromium oxide with a pore diameter of 7.9 nm (AK Sinha, et al., Angew. Chem. Int. Ed., 2005, 44:271; AK Sinha, et al., Appl. Catal. B, 2007, 70:417). Yan et al. used solid sols of citric acid and chromium nitrate mixtures in different molar ratios to prepare chromium oxides with different shapes, sizes, and pore structures by thermal decomposition under closed conditions (ZF Yan, et al., J. Phys. Chem. B, 2006, 110:178). Guzman et al. prepared mesoporous yttrium oxide with a specific surface area of 90 m² /g and a pore diameter of 6.5 nm by using amino acid-modified yttrium oxide sol and P123 as a template (J. Guzman, et al., Chem. Commun., 2005, 743), Wang et al. used sodium dodecyl sulfate as template agent, nitrate as metal source, and urea as precipitant to prepare mesoporous samarium oxide and Erbium oxide (Y. Wang, et al., Ultrasonics Sonochem., 2002, 9: 285). However, the above method also has some limitations, such as difficulty in controlling the hydrolysis rate of the metal salt, easy collapse of the pores when the template is removed by calcination, and poor universality of the method. Thus, the applications of the obtained mesoporous metal oxides are greatly limited.

发明内容Contents of the invention

本发明的目的在于克服以往其它有机模板法所得样品孔结构规整度较差、孔道易塌陷、方法普适性差等缺点。利用有序介孔分子筛作硬模板剂，借助超声波的作用使金属盐分子能有效地分散到介孔分子筛的孔道内，再经过煅烧、洗涤、干燥等过程得到目标产物。 The purpose of the present invention is to overcome the disadvantages of poor sample pore structure regularity, easy collapse of channels and poor universality of the method obtained by other organic template methods in the past. Using ordered mesoporous molecular sieves as hard templates, metal salt molecules can be effectively dispersed into the pores of mesoporous molecular sieves by means of ultrasonic waves, and then the target product can be obtained through calcination, washing, drying and other processes. the

本发明先以正硅酸乙酯(TEOS)为原料，以三嵌段共聚物(EO)₂₀(PO)₇₀(EO)₂₀(Pluronic P123)为模板剂，以正丁醇为辅助溶剂，通过水热反应合成出立方相介孔氧化硅，然后以其为硬模板剂，以无机金属盐为前驱物，得到具有高度有序孔结构和高比表面积的介孔金属氧化物。 In the present invention, tetraethyl orthosilicate (TEOS) is used as raw material, triblock copolymer (EO)₂₀ (PO)₇₀ (EO)₂₀ (Pluronic P123) is used as template, and n-butanol is used as auxiliary solvent. Cubic phase mesoporous silica was synthesized by hydrothermal reaction, and then used as a hard template and inorganic metal salt as a precursor to obtain a mesoporous metal oxide with a highly ordered pore structure and a high specific surface area.

具体步骤如下： Specific steps are as follows:

(1)参照文献(Freddy K.，et al.Chem.Commun.，2003，2136)方法，先合成立方相介孔氧化硅(KIT-6)粉末。其合成过程为：在室温下，向0.5～0.8mol/L的盐酸溶液中加入三嵌段共聚物(EO)₂₀(PO)₇₀(EO)₂₀(Pluronic P123)和正丁醇，搅拌使之溶解，得到P123和正丁醇均为2～5wt％的混合溶液，在35℃保温1小时，再加入正硅酸乙酯(TEOS)或硅酸钠做硅源，使硅的含量达到4～10wt％。保持35℃下继续搅拌24小时。将所得混合物转移至自压釜中，放入恒温箱并在100℃恒温水热处理24小时，经过滤、去离子水、乙醇洗涤后于60～70℃干燥20～24小时，得到白色固体粉末。将所得白色固体粉末在马弗炉中以1℃/min的速率从室温升至550℃并在550℃下恒温灼烧4小时，得到立方相介孔氧化硅(KIT-6)白色粉末。 (1) Referring to the literature (Freddy K., et al. Chem. Commun., 2003, 2136) method, the cubic phase mesoporous silica (KIT-6) powder was first synthesized. The synthesis process is: at room temperature, add triblock copolymer (EO)₂₀ (PO)₇₀ (EO)₂₀ (Pluronic P123) and n-butanol to 0.5-0.8 mol/L hydrochloric acid solution, stir to dissolve , to obtain a mixed solution in which P123 and n-butanol are 2-5wt%, keep it warm at 35°C for 1 hour, then add orthoethyl silicate (TEOS) or sodium silicate as a silicon source, so that the silicon content reaches 4-10wt% . Stirring was continued at 35°C for 24 hours. The resulting mixture was transferred to an autoclave, placed in a constant temperature box, and subjected to constant temperature hydrothermal treatment at 100°C for 24 hours, filtered, washed with deionized water and ethanol, and dried at 60-70°C for 20-24 hours to obtain a white solid powder. The resulting white solid powder was raised from room temperature to 550°C at a rate of 1°C/min in a muffle furnace and burned at a constant temperature of 550°C for 4 hours to obtain a cubic phase mesoporous silica (KIT-6) white powder.

(2)将上述立方相介孔氧化硅粉末加入到浓度为0.12～0.40mol/L的金属盐的50～95wt％乙醇溶液形成混合液中，超声分散90～120分钟后，再搅拌使该混合液于40～50℃蒸发至干，然后置于管式炉中以1℃/min的速率在氮气气氛中升温至400～850℃，且在该温度下恒温4小时，得到介孔氧化物前驱体粉末；其中立方相介孔氧化硅粉末与金属盐的摩尔比为7 －14； (2) Add the above-mentioned cubic phase mesoporous silica powder to a 50-95wt% ethanol solution of a metal salt with a concentration of 0.12-0.40mol/L to form a mixed solution, and after ultrasonic dispersion for 90-120 minutes, stir again to make the mixture The liquid is evaporated to dryness at 40-50°C, then placed in a tube furnace and heated to 400-850°C in a nitrogen atmosphere at a rate of 1°C/min, and kept at this temperature for 4 hours to obtain a mesoporous oxide precursor Bulk powder; wherein the molar ratio of cubic phase mesoporous silica powder to metal salt is 7 -14;

(3)用10wt％的HF溶液洗涤所得介孔氧化物前驱体粉末以除去立方相介孔氧化硅模板剂，再在60～70℃干燥20～24小时后，即得到介孔金属氧化物粉末。 (3) Wash the obtained mesoporous oxide precursor powder with 10wt% HF solution to remove the cubic phase mesoporous silica template, and then dry it at 60-70°C for 20-24 hours to obtain the mesoporous metal oxide powder . the

利用X射线衍射仪(XRD)、N₂吸附-脱附、透射电子显微镜(TEM)及选区电子衍射(SAED)等技术进行表征所得产物介孔金属氧化物的物理性 质。结果表明，采用本方法所制得样品是具有有序孔道结构和高比表面积的介孔金属氧化物，比表面积为120～280m²/g，孔径为3～20nm。 The physical properties of the obtained mesoporous metal oxides were characterized by X-ray diffractometer (XRD),_N2 adsorption-desorption, transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The results show that the sample prepared by this method is a mesoporous metal oxide with ordered pore structure and high specific surface area, the specific surface area is 120-280m² /g, and the pore diameter is 3-20nm.

本发明提供的利用硬模板剂合成高比表面积有序介孔金属氧化物的方法，其特征在于，具体合成过程如下： The method for synthesizing ordered mesoporous metal oxides with high specific surface area using hard templates provided by the present invention is characterized in that the specific synthesis process is as follows:

(1)先合成硬模板剂立方相介孔氧化硅KIT-6粉末； (1) Synthesize hard template cubic phase mesoporous silica KIT-6 powder first;

(2)将上述立方相介孔氧化硅KIT-6粉末加入到浓度为0.12～0.40mol/L的金属盐的50～95wt％乙醇溶液形成混合液中，超声分散90～120分钟后，再搅拌使该混合液于40～50℃蒸发至干，然后置于管式炉中以1℃/min的速率在氮气气氛中升温至400～850℃，且在该温度下恒温4小时，得到介孔氧化物前驱体粉末；其中立方相介孔氧化硅粉末与金属盐的摩尔比为7-14；所述金属盐为硝酸铬、重铬酸铵、草酸铬、硝酸钐和硝酸铕之一； (2) Add the above-mentioned cubic phase mesoporous silica KIT-6 powder into the mixed solution of 50-95wt% ethanol solution of metal salt with a concentration of 0.12-0.40mol/L, ultrasonically disperse for 90-120 minutes, and then stir The mixture was evaporated to dryness at 40-50°C, then placed in a tube furnace at a rate of 1°C/min to raise the temperature to 400-850°C in a nitrogen atmosphere, and kept at this temperature for 4 hours to obtain mesoporous Oxide precursor powder; wherein the molar ratio of cubic phase mesoporous silicon oxide powder to metal salt is 7-14; the metal salt is one of chromium nitrate, ammonium dichromate, chromium oxalate, samarium nitrate and europium nitrate;

(3)用10wt％的HF溶液洗涤所得介孔氧化物前驱体粉末以除去立方相介孔氧化硅模板剂，再在60～70℃干燥20～24小时后，即得到介孔金属氧化物粉末。 (3) Wash the obtained mesoporous oxide precursor powder with 10wt% HF solution to remove the cubic phase mesoporous silica template, and then dry it at 60-70°C for 20-24 hours to obtain the mesoporous metal oxide powder . the

本发明利用立方相介孔氧化硅(KIT-6)粉末为硬模板剂，能有效地克服现有技术不足，得到高比表面积的有序孔道结构的介孔金属氧化物。本发明方法的制备成本低，操作过程简便，目标产物孔径分布窄，比表面积大，并可调变金属盐种类得到不同组成的金属氧化物。目前还没有文献和专利报道过本发明的方法。 The present invention uses cubic phase mesoporous silicon oxide (KIT-6) powder as a hard template, can effectively overcome the shortcomings of the prior art, and obtain mesoporous metal oxides with a high specific surface area and an ordered pore structure. The method of the invention has low preparation cost, simple and convenient operation process, narrow pore size distribution of the target product, large specific surface area, and can adjust the metal salt type to obtain metal oxides with different compositions. There are no documents and patents to report the method of the present invention. the

附图说明Description of drawings

为进一步了解本发明，下面以实施例作详细说明，并给出附图描述本发明得到的高比表面积介孔金属氧化物，其中： For further understanding of the present invention, the following are described in detail with the examples, and the accompanying drawings describe the high specific surface area mesoporous metal oxide obtained by the present invention, wherein:

图1(a)、1(b)分别为实施例1样品KIT-6纯硅分子筛和介孔氧化铬的XRD谱图，其中的插图分别为其对应的小角度XRD谱图。 Figures 1(a) and 1(b) are the XRD spectra of samples KIT-6 pure silicon molecular sieve and mesoporous chromium oxide in Example 1, respectively, and the insets are their corresponding small-angle XRD spectra. the

图2(a)、2(b)、2(c)分别为实施例1样品KIT-6纯硅分子筛和介孔氧化铬的TEM照片和介孔氧化铬样品的HRTEM照片，其中的插图为该样品的SAED图案。 Fig. 2 (a), 2 (b), 2 (c) are respectively the TEM photo ofembodiment 1 sample KIT-6 pure silicon molecular sieve and mesoporous chromium oxide and the HRTEM photo of mesoporous chromium oxide sample, and the illustration wherein is this SAED pattern of the samples. the

图3(a)、3(b)分别为实施例2样品介孔氧化铬的TEM照片和HRTEM照片。 3(a) and 3(b) are the TEM photo and HRTEM photo of the sample mesoporous chromium oxide in Example 2, respectively. the

图4(a)、4(b)分别为实施例3样品介孔氧化铬的TEM照片和HRTEM照片。 Figures 4(a) and 4(b) are the TEM photo and HRTEM photo of the sample mesoporous chromium oxide in Example 3, respectively. the

图5(a)、5(b)、5(c)、5(d)分别为实施例4介孔氧化钐的XRD谱图、N₂吸附-脱附等温线、TEM照片和HRTEM照片，其中5(a)、5(b)和5(d)中的插图分别为该样品的小角XRD谱图、孔径分布曲线和SAED图案。 Fig. 5 (a), 5 (b), 5 (c), 5 (d) areembodiment 4 mesoporous samarium oxide respectively XRD spectrogram, N_Adsorption -desorption isotherm, TEM photograph and HRTEM photograph, wherein The insets in 5(a), 5(b) and 5(d) are the small-angle XRD spectrum, pore size distribution curve and SAED pattern of this sample, respectively.

图6(a)、6(b)、6(c)分别为实施例5介孔氧化铕的XRD谱图、N₂吸附-脱附等温线、和TEM照片，其中6(a)、6(b)和6(c)中的插图分别为该样品的小角XRD谱图、孔径分布曲线和SAED图案。 Fig. 6 (a), 6 (b), 6 (c) are the XRD spectrogram, N of embodiment₅ mesoporous europium oxide respectively Adsorption-desorption isotherm, and TEM photo, wherein 6 (a), 6 ( The insets in b) and 6(c) are the small-angle XRD spectrum, pore size distribution curve, and SAED pattern of the sample, respectively.

具体实施方式Detailed ways

本发明的具体实施步骤如下： Concrete implementation steps of the present invention are as follows:

实施例1：在室温下，向100mL 0.5mol/L盐酸溶液中加入2.7g三嵌段共聚物(EO)₂₀(PO)₇₀(EO)₂₀(Pluronic P123)，搅拌至溶解，缓慢(2℃/min)升温至35℃，在搅拌情况下加入2.8g正丁醇，并保持35℃搅拌1小时，再向上述溶液中加入5.8g正硅酸乙酯(各物质的摩尔比为：正硅酸乙酯∶三嵌段共聚物(EO)₂₀(PO)₇₀(EO)₂₀∶盐酸∶去离子水∶正丁醇＝1∶0.017∶1.83∶195∶1.31)，保持35℃搅拌24小时，转入自压釜在100℃水热24小时，经过滤、去离子水和乙醇洗涤后在60℃下干燥，然后在马弗炉中程序升温(1℃/min)至550℃并在550℃下灼烧4小时，得到立方相介孔氧化硅(KIT-6)白色粉末。所得KIT-6的比表面积为780m²/g，平均孔径为3nm。 Example 1: At room temperature, add 2.7g triblock copolymer (EO)₂₀ (PO)₇₀ (EO)₂₀ (Pluronic P123) to 100mL 0.5mol/L hydrochloric acid solution, stir until dissolved, slowly (2°C /min) to heat up to 35°C, add 2.8g n-butanol while stirring, and keep stirring at 35°C for 1 hour, then add 5.8g tetraethyl orthosilicate to the above solution (the molar ratio of each substance is: orthosilicon ethyl acetate: triblock copolymer (EO)₂₀ (PO)₇₀ (EO)₂₀ : hydrochloric acid: deionized water: n-butanol = 1: 0.017: 1.83: 195: 1.31), kept stirring at 35°C for 24 hours, Transfer to an autoclave and heat at 100°C for 24 hours, filter, wash with deionized water and ethanol, and dry at 60°C, then program the temperature in a muffle furnace (1°C/min) to 550°C and heat at 550°C Burning at low temperature for 4 hours, the cubic phase mesoporous silica (KIT-6) white powder was obtained. The obtained KIT-6 had a specific surface area of 780 m² /g and an average pore diameter of 3 nm.

将1.0g硝酸铬加至10mL无水乙醇中，搅拌溶解后将0.5g KIT-6白色粉末加至上述溶液中，超声分散100分钟后，再将混合物在磁力搅拌下于40℃蒸发至干，得到的固体在氮气气氛(氮气流量为30mL/min)中以1℃/min的速率程序升温至400℃并在400℃下恒温4小时，最后用10wt％HF溶液洗涤除去硅模板，再在60℃干燥24小时后，即得介孔多晶氧化铬粉末，其比表面积为124m²/g，平均孔径为13nm。 Add 1.0g of chromium nitrate to 10mL of absolute ethanol, stir to dissolve, add 0.5g of KIT-6 white powder to the above solution, ultrasonically disperse for 100 minutes, then evaporate the mixture to dryness at 40°C under magnetic stirring, The obtained solid was heated up to 400° C. at a rate of 1° C./min in a nitrogen atmosphere (nitrogen flow rate of 30 mL/min) and kept at 400° C. for 4 hours. Finally, the silicon template was removed by washing with 10 wt % HF solution, and then at 60 After drying at ℃ for 24 hours, the mesoporous polycrystalline chromium oxide powder was obtained, with a specific surface area of 124m² /g and an average pore diameter of 13nm.

实施例2：硬模板KIT-6合成同实施例1。将0.5g重铬酸铵加至10mL 50wt％的乙醇溶液中，搅拌溶解后将0.5g KIT-6白色粉末加至上述溶液中，超声分散100分钟后，再将混合物在磁力搅拌下于40℃蒸发至干，得到的固体 在氮气气氛(氮气流量为30mL/min)中以1℃/min的速率程序升温至400℃并在400℃下恒温4小时，最后用10wt％HF溶液洗涤除去硅模板，再在60℃干燥24小时后，即得介孔多晶氧化铬粉末，其比表面积为167m²/g，平均孔径为7nm。 Example 2: The synthesis of hard template KIT-6 is the same as that in Example 1. Add 0.5g of ammonium dichromate to 10mL of 50wt% ethanol solution, stir to dissolve, add 0.5g of KIT-6 white powder to the above solution, ultrasonically disperse for 100 minutes, and then place the mixture at 40°C under magnetic stirring Evaporated to dryness, the obtained solid was heated to 400°C at a rate of 1°C/min in a nitrogen atmosphere (nitrogen flow rate of 30mL/min) and kept at 400°C for 4 hours, and finally washed with 10wt% HF solution to remove the silicon template , and then dried at 60°C for 24 hours to obtain mesoporous polycrystalline chromium oxide powder with a specific surface area of 167m² /g and an average pore diameter of 7nm.

实施例3：硬模板KIT-6合成同实施例1。将1.2g草酸铬加至10mL无水乙醇中，搅拌溶解后将0.5g KIT-6白色粉末加至上述溶液中，超声分散100分钟后，再将混合物在磁力搅拌下于40℃蒸发至干，得到的固体在氮气气氛(氮气流量为30mL/min)中以1℃/min的速率程序升温至400℃并在400℃下恒温4小时，最后用10wt％HF溶液洗涤除去硅模板，再在60℃干燥24小时后，即得介孔多晶氧化铬粉末，其比表面积为125m²/g，平均孔径为15nm。 Example 3: The synthesis of hard template KIT-6 is the same as that in Example 1. Add 1.2g of chromium oxalate to 10mL of absolute ethanol, stir to dissolve, add 0.5g of KIT-6 white powder to the above solution, ultrasonically disperse for 100 minutes, then evaporate the mixture to dryness at 40°C under magnetic stirring, The obtained solid was heated up to 400° C. at a rate of 1° C./min in a nitrogen atmosphere (nitrogen flow rate of 30 mL/min) and kept at 400° C. for 4 hours. Finally, the silicon template was removed by washing with 10 wt % HF solution, and then at 60 After drying at ℃ for 24 hours, the mesoporous polycrystalline chromium oxide powder was obtained, with a specific surface area of 125m² /g and an average pore diameter of 15nm.

实施例4：硬模板KIT-6合成同实施例1。将1.1g硝酸钐加至10mL无水乙醇中，搅拌溶解后将0.5g KIT-6白色粉末加至上述溶液中，超声分散100分钟后，再将混合物在磁力搅拌下于40℃蒸发至干，得到的固体在氮气气氛(氮气流量为30mL/min)中以1℃/min的速率程序升温至850℃并在850℃下恒温4小时，最后用10wt％HF溶液洗涤除去硅模板，再在60℃干燥24小时后，即得有序介孔多晶氧化钐，其比表面积为280m²/g，平均孔径为3nm。从图5中可看出该样品的孔径分布较窄，吸-脱附曲线有明显的介孔材料所具有的特征回滞环，且孔道分布有序度高， Example 4: The synthesis of hard template KIT-6 is the same as that in Example 1. Add 1.1g of samarium nitrate to 10mL of absolute ethanol, stir to dissolve, add 0.5g of KIT-6 white powder to the above solution, ultrasonically disperse for 100 minutes, then evaporate the mixture to dryness at 40°C under magnetic stirring, The obtained solid was heated up to 850° C. at a rate of 1° C./min in a nitrogen atmosphere (nitrogen flow rate of 30 mL/min) and kept at 850° C. for 4 hours. Finally, the silicon template was removed by washing with 10 wt % HF solution, and then at 60 After drying at ℃ for 24 hours, the ordered mesoporous polycrystalline samarium oxide was obtained, with a specific surface area of 280m² /g and an average pore diameter of 3nm. It can be seen from Figure 5 that the sample has a narrow pore size distribution, and the adsorption-desorption curve has obvious hysteresis loops characteristic of mesoporous materials, and the pore distribution is highly ordered.

实施例5：硬模板KIT-6合成同实施例1。将1.1g硝酸铕加至10mL去离子水中，搅拌溶解后将0.5g KIT-6白色粉末加至上述溶液中，超声分散100分钟后，再将混合物在磁力搅拌下于40℃蒸发至干，得到的固体在氮气气氛(氮气流量为30mL/min)中以1℃/min的速率程序升温至750℃并在750℃下恒温4小时，最后用10wt％HF溶液洗涤除去硅模板，再在60℃干燥24小时后，即得有序介孔多晶氧化铕，其比表面积为144m²/g，平均孔径为19nm。从图6可看出该样品的吸-脱附曲线的回滞环明显，孔径分布集中在19nm附近，孔道的有序度较好。 Example 5: The synthesis of hard template KIT-6 is the same as that in Example 1. Add 1.1g of europium nitrate to 10mL of deionized water, stir to dissolve, add 0.5g of KIT-6 white powder to the above solution, ultrasonically disperse for 100 minutes, and then evaporate the mixture to dryness at 40°C under magnetic stirring to obtain The solid was heated up to 750°C at a rate of 1°C/min in a nitrogen atmosphere (nitrogen flow rate of 30mL/min) and kept at 750°C for 4 hours, and finally washed with 10wt% HF solution to remove the silicon template, and then heated at 60°C After drying for 24 hours, ordered mesoporous polycrystalline europium oxide was obtained, with a specific surface area of 144 m² /g and an average pore diameter of 19 nm. It can be seen from Figure 6 that the hysteresis loop of the adsorption-desorption curve of this sample is obvious, the pore size distribution is concentrated around 19nm, and the order of the pores is good.

Claims (1)

1. utilize the method for hard mould agent synthesizing high specific surface area ordered mesoporous metal oxide, it is characterized in that, concrete building-up process is as follows:

(1) the earlier synthetic cubic-phase mesoporous silicon oxide powder of hard mould agent; Building-up process is: at room temperature, add triblock copolymer (EO) in the hydrochloric acid soln of 0.5～0.8mol/L₂₀(PO)₇₀(EO)₂₀And propyl carbinol, stir and make it dissolving, obtain triblock copolymer (EO)₂₀(PO)₇₀(EO)₂₀P123 and propyl carbinol are the mixing solutions of 2～5wt%, 35 ℃ of insulations 1 hour, add tetraethoxy or water glass again and do the silicon source, make the content of silicon reach 4～10wt%; Keep 35 ℃ to continue down to stir 24 hours; The gained mixture is transferred to from pressing in the still, puts into thermostat container and 100 ℃ of thermostat(t)ed water thermal treatments 24 hours, after filtration, behind the deionized water, washing with alcohol in 60～70 ℃ of dryings 20～24 hours, obtain the white solid powder; Gained white solid powder is risen to 550 ℃ and 550 ℃ of following constant temperature calcinations 4 hours with the speed of 1 ℃/min from room temperature in retort furnace, obtain cubic-phase mesoporous silicon oxide KIT-6 white powder;

(2) above-mentioned cubic-phase mesoporous silicon oxide KIT-6 powder being joined concentration is that 50～95wt% ethanolic soln of the metal-salt of 0.12～0.40mol/L forms in the mixed solution, behind the ultra-sonic dispersion 90～120 minutes, restir makes this mixed solution be evaporated to dried in 40～50 ℃, place tube furnace to be warming up to 400～850 ℃ at nitrogen atmosphere then with the speed of 1 ℃/min, and constant temperature is 4 hours under this temperature, obtains the mesopore oxide precursor powder; The mol ratio of wherein cubic-phase mesoporous silicon oxide powder and metal-salt is 7-14; Described metal-salt is one of chromium nitrate, ammonium dichromate, chromium+oxalic acid, samaric nitrate and europium nitrate;

(3) with the HF solution washing gained mesopore oxide precursor powder of 10wt% to remove cubic-phase mesoporous silicon oxide template, after 20～24 hours, promptly obtain the mesopore metal oxide powder 60～70 ℃ of dryings again.

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