透明PMOs凝胶独石的控制制备及其光学性能
发布时间：2018-07-31 13:11
【摘要】：周期性介孔有机二氧化硅（PMOs）是采用桥联倍半硅氧烷作前驱体，在表面活性剂模板作用下合成的一类新型有机-无机杂化介孔材料。由于其合成思想至少允许将两种不同的功能化单元同步放置在介孔结构中两个空间上相分离的区域—孔壁骨架和介孔孔道，使它在各种新型复合功能材料的研究领域显示出更为广泛的应用前景。显然，若能控制合成具有宏观形貌及尺寸可调的透明PMOs凝胶独石，将较常规的粉体材料具有更好的可操作性，在新型光、电、磁性器件及固体染料激光器、传感器等的研究领域具有重要意义，而目前PMOs材料的合成及应用研究仍局限于粉体或薄膜形貌。 基于上述思想，本工作采用商品化的亚乙基桥联倍半硅氧烷作前驱体，在酸性条件下以不同非离子嵌段共聚物类表面活性剂作模板剂，系统开展了亚乙基桥联的透明PMOs凝胶独石的无裂纹化控制制备技术和规律研究，并将具有不同结构和物性的有机染料如罗丹明6G（Rh6G）、7-羟基-4-甲基香豆素（7H4MC）和亚甲基蓝（MB）等采用直接合成的方式引入透明PMOs凝胶孔道，初步研究了染料掺杂后凝胶的光学性能。主要研究结果如下： 1、首先以F127作模板剂，通过对合成参数和制备条件的全面筛选和评价，在40℃恒温敞口干燥的条件下首次控制合成了宏观尺寸可随容器形状加以调节的透明PMOs凝胶独石。通过对不同脱模板方法如乙醇萃取，水萃取，焙烧及高氯酸铵氧化等处理后样品的N2吸附和TG分析，发现高氯酸铵氧化法是一种更为有效的脱模板方法，且在脱模板后仍能保持凝胶整体形貌的完整。其N2吸附等温线呈含H2型滞后环的IV型曲线，暗示凝胶可能含有与SBA-16相似的类笼形介孔结构。对Rh6G掺杂后凝胶的UV-vis及荧光光谱研究发现，Rh6G在PMOs凝胶中的二聚倾向明显减弱，发射光谱蓝移。说明PMOs凝胶独石中模板剂的存在有利于染料分子的更好分散和稳定，进而改善材料的发光性能。 2、采用P123作模板剂，以甲醇作助溶剂，在14.5-35.5wt%的模板剂浓度范围内控制合成了具有类SBA-15结构的二维六方相亚乙基桥联的透明PMOs透明凝胶独石。将7H4MC香豆素染料引入透明PMOs凝胶独石后的光学性能研究显示，7H4MC/SiO-42比在10-2-10间调节时，随染料浓度的增加，，发射光谱仅轻微红移但其发光强度却显著增加。在固定7H4MC/SiO2比为10-3时，发现过高的模板剂浓度反而会因凝胶中染料占比的降低而使发光强度减弱，说明模板剂的存在不仅有利于更高浓度染料分子的分散，而且染料掺杂的浓度与所使用模板剂的浓度间在保证PMOs凝胶独石整体完整的前提存在一定的最佳匹配关系。 3、采用Brij56作模板剂，乙醇作助溶剂，在模板剂浓度为5.2-35.5wt%的范围内控制合成了亚乙基改性的PMOs透明凝胶独石材料。研究发现引入长链醇，如丁、戊、己醇或调节其浓度，均可在保证凝胶整体透明完整的前提下，使凝胶的孔径有所增加。MB掺杂PMO凝胶后的紫外-可见及荧光光谱研究结果显示，模板剂的存在同样有助于MB染料分子的高浓度分散，进而使染料分子间二聚的趋势减弱，发射光谱明显蓝移，有助于材料光学性能的改善
[Abstract]:Periodic mesoporous organic silica (PMOs) is a new type of organic-inorganic hybrid mesoporous material which is synthesized under the action of surfactant template with bridged sesquioxane as a precursor and at least two different functional units are allowed to be placed in two space separated areas in the mesoporous structure. The pore wall skeleton and mesoporous channel make it more widely applied in the research field of various new composite functional materials. Obviously, if the transparent PMOs gel with macro morphologies and adjustable sizes can be controlled, it will have better operability than the conventional powder materials in the new light, electricity, magnetic devices and solids. The research fields of dye lasers and sensors are of great significance, but the synthesis and application of PMOs are still limited to the morphology of powders or thin films.
Based on the above thought, a commercialized ethylenediethylsilsesquioxane is used as a precursor, and under acidic conditions, different nonionic block copolymer surfactants are used as templates. The preparation technology and law study of the transparent PMOs gel single stone without crack control are systematically carried out, and the different structures will have different structures. The organic dyes, such as Luo Danming 6G (Rh6G), 7- hydroxyl -4- methyl coumarin (7H4MC) and Ya Jiaji blue (MB), are introduced into the transparent PMOs gel channel by direct synthesis, and the optical properties of the gels after the dye doping are preliminarily studied. The main results are as follows:
1, first, by using F127 as a template, through the comprehensive screening and evaluation of the synthetic parameters and preparation conditions, the transparent PMOs gel monolith, which can be adjusted with the shape of the container, is synthesized for the first time under the condition of constant temperature and drying at 40 C. Through the different deformable methods such as ethanol extraction, water extraction, calcination and ammonium perchlorate oxidation The N2 adsorption and TG analysis of the samples after treatment showed that the ammonium perchlorate oxidation method was a more effective deformable method, and the whole morphology of the gel could remain intact after the deformability. The N2 adsorption isotherm showed a IV type curve containing the H2 type hysteresis loop, suggesting that the gel may contain a cage like mesoporous structure similar to that of SBA-16. The doping of the gel to Rh6G is possible. The UV-vis and fluorescence spectra of the post gel show that the two polymerization tendency of Rh6G in PMOs gel weakens obviously and the emission spectrum is blue shift. It shows that the presence of template in PMOs gel is beneficial to the better dispersion and stability of dye molecules, and thus improve the luminescence properties of the materials.
2, using P123 as a template, using methanol as a cosolvent, the transparent PMOs transparent gel single stone with a two dimensional six square phase ethyl bridge with SBA-15 like structure is controlled within the concentration range of the template of 14.5-35.5wt%. The optical properties of 7H4MC coumarin dye introduced into the transparent PMOs gel show that 7H4MC/SiO-42 is compared to 10-2-10 When the dye concentration increases, the emission spectrum is only slightly red shift but its luminous intensity increases significantly. When the fixed 7H4MC/SiO2 ratio is 10-3, it is found that the high concentration of the template will weaken the luminescence intensity because of the decrease of the dye occupation ratio in the gel, indicating that the presence of the template is not only beneficial to the higher concentration of dye molecules. Moreover, there is a certain optimum matching relationship between the concentration of dye doping and the concentration of template used to ensure the integrity of PMOs gel monolith.
3, Brij56 is used as a template and ethanol as a cosolvent to control the synthesis of ethyl modified PMOs transparent gel monolith in the range of template concentration of 5.2-35.5wt%. It is found that the introduction of long chain alcohols, such as butyl, amyl, hexanol, or its concentration, can increase the pore size of the gel under the premise of transparent and complete gel whole body. The results of UV visible and fluorescence spectra of MB doped PMO gel show that the existence of template is also helpful to the high dispersion of MB dye molecules, and the trend of the two polymerization of dye molecules is weakened and the emission spectrum is obviously blue shift, which helps to improve the optical properties of the materials.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.4;TQ427.26
本文编号：2155678
[Abstract]:Periodic mesoporous organic silica (PMOs) is a new type of organic-inorganic hybrid mesoporous material which is synthesized under the action of surfactant template with bridged sesquioxane as a precursor and at least two different functional units are allowed to be placed in two space separated areas in the mesoporous structure. The pore wall skeleton and mesoporous channel make it more widely applied in the research field of various new composite functional materials. Obviously, if the transparent PMOs gel with macro morphologies and adjustable sizes can be controlled, it will have better operability than the conventional powder materials in the new light, electricity, magnetic devices and solids. The research fields of dye lasers and sensors are of great significance, but the synthesis and application of PMOs are still limited to the morphology of powders or thin films.
Based on the above thought, a commercialized ethylenediethylsilsesquioxane is used as a precursor, and under acidic conditions, different nonionic block copolymer surfactants are used as templates. The preparation technology and law study of the transparent PMOs gel single stone without crack control are systematically carried out, and the different structures will have different structures. The organic dyes, such as Luo Danming 6G (Rh6G), 7- hydroxyl -4- methyl coumarin (7H4MC) and Ya Jiaji blue (MB), are introduced into the transparent PMOs gel channel by direct synthesis, and the optical properties of the gels after the dye doping are preliminarily studied. The main results are as follows:
1, first, by using F127 as a template, through the comprehensive screening and evaluation of the synthetic parameters and preparation conditions, the transparent PMOs gel monolith, which can be adjusted with the shape of the container, is synthesized for the first time under the condition of constant temperature and drying at 40 C. Through the different deformable methods such as ethanol extraction, water extraction, calcination and ammonium perchlorate oxidation The N2 adsorption and TG analysis of the samples after treatment showed that the ammonium perchlorate oxidation method was a more effective deformable method, and the whole morphology of the gel could remain intact after the deformability. The N2 adsorption isotherm showed a IV type curve containing the H2 type hysteresis loop, suggesting that the gel may contain a cage like mesoporous structure similar to that of SBA-16. The doping of the gel to Rh6G is possible. The UV-vis and fluorescence spectra of the post gel show that the two polymerization tendency of Rh6G in PMOs gel weakens obviously and the emission spectrum is blue shift. It shows that the presence of template in PMOs gel is beneficial to the better dispersion and stability of dye molecules, and thus improve the luminescence properties of the materials.
2, using P123 as a template, using methanol as a cosolvent, the transparent PMOs transparent gel single stone with a two dimensional six square phase ethyl bridge with SBA-15 like structure is controlled within the concentration range of the template of 14.5-35.5wt%. The optical properties of 7H4MC coumarin dye introduced into the transparent PMOs gel show that 7H4MC/SiO-42 is compared to 10-2-10 When the dye concentration increases, the emission spectrum is only slightly red shift but its luminous intensity increases significantly. When the fixed 7H4MC/SiO2 ratio is 10-3, it is found that the high concentration of the template will weaken the luminescence intensity because of the decrease of the dye occupation ratio in the gel, indicating that the presence of the template is not only beneficial to the higher concentration of dye molecules. Moreover, there is a certain optimum matching relationship between the concentration of dye doping and the concentration of template used to ensure the integrity of PMOs gel monolith.
3, Brij56 is used as a template and ethanol as a cosolvent to control the synthesis of ethyl modified PMOs transparent gel monolith in the range of template concentration of 5.2-35.5wt%. It is found that the introduction of long chain alcohols, such as butyl, amyl, hexanol, or its concentration, can increase the pore size of the gel under the premise of transparent and complete gel whole body. The results of UV visible and fluorescence spectra of MB doped PMO gel show that the existence of template is also helpful to the high dispersion of MB dye molecules, and the trend of the two polymerization of dye molecules is weakened and the emission spectrum is obviously blue shift, which helps to improve the optical properties of the materials.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.4;TQ427.26
【参考文献】
相关期刊论文 前2条
1 奚红霞,黄仲涛;凝胶的干燥[J];膜科学与技术;1997年01期
2 朱桂茹;杨启华;李灿;;乙烷桥键介孔材料的制备及其在反相液相色谱中的应用[J];色谱;2007年04期
本文编号：2155678
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