Colloidal Particle Growth in Silica Xerogels

二氧化硅干凝胶中胶体颗粒的生长

• 批准号: 9510607
• 负责人: Simeen Sattar
• 金额: $ 6万
• 依托单位: Bard College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-12-15 至 1997-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9510607&HistoricalAwards=false
• 关键词: Colloidal; Particle; Growth; Silica; Xerogels

Abstract 9510607 Simeen A new strategy is devised for making colloidal particles dispersed within an inorganic or organic matrix. The sol-gel process is combined with methods for making colloidal particles by homogeneous precipitation from electrolyte solutions. The feasibility of this approach has been demonstrated by successful preparation of a material consisting of large numbers of 0.1-1 micrometer chromium hydroxide spheres embedded within a silica xerogel. Homogeneous precipitation offers the possibility of making a wide variety of particles and the means for exercising systematic control over particle morphology. The goals of the proposed research are to determine whether this technique can be extended to generate particles with different compositions within gels; whether it is possible to create crystalline particles; and whether the metal salt particles can be reduced to metal. Other experiments will investigate the role of the gel matrix in controlling particle size. %%% Synthesis of composite materials consisting of colloidal particles dispersed within an inorganic or organic matrix is of considerable interest because of applications in catalysis and optics, among other areas. A new strategy for making such composites has been devised that combines the sol-gel process with methods for making colloidal particles by homogeneous precipitation from electrolyte solutions. The feasibility of this approach has been demonstrated by successful preparation of a material consisting of large numbers of 0.1-1 micrometer chromium hydroxide spheres embedded within a silica xerogel. Homogeneous precipitation offers the possibility of making a wide variety of particles and the means for exercising systematic control over particle morphology. The goals of the research described in this proposal are to determine whether this technique can be extended to generate particles with different compositions within gels; whether it is possible to create crystalline particles; and whether the metal salt particles can be reduced to metal.

设计了一种使胶体颗粒分散在无机或有机基质中的新策略。溶胶-凝胶法结合了从电解质溶液中均匀沉淀制备胶体颗粒的方法。这种方法的可行性已经被成功地制备了一种材料，该材料由大量0.1-1微米的氢氧化铬球嵌入二氧化硅凝胶中组成。均匀沉淀提供了制造各种各样的颗粒的可能性，以及对颗粒形态进行系统控制的手段。拟议研究的目标是确定这种技术是否可以扩展到在凝胶中产生具有不同组成的颗粒；是否有可能制造结晶粒子；以及金属盐颗粒能否还原为金属。其他实验将研究凝胶基质在控制颗粒大小方面的作用。由分散在无机或有机基质中的胶体颗粒组成的复合材料的合成由于在催化和光学等领域的应用而引起了相当大的兴趣。一种制造这种复合材料的新策略已经被设计出来，它结合了溶胶-凝胶工艺和从电解质溶液中均匀沉淀制备胶体颗粒的方法。这种方法的可行性已经被成功地制备了一种材料，该材料由大量0.1-1微米的氢氧化铬球嵌入二氧化硅凝胶中组成。均匀沉淀提供了制造各种各样的颗粒的可能性，以及对颗粒形态进行系统控制的手段。本提案中描述的研究目标是确定该技术是否可以扩展到在凝胶中产生具有不同组成的颗粒；是否有可能制造结晶粒子；以及金属盐颗粒能否还原为金属。