基于冰模板法构筑孔道结构的合成策略及研究进展

Synthesis strategy and research progress of pore structure based on ice-templating method

摘要:

冰模板法也称为定向冷冻法或冷冻铸造法，其原理是利用冷冻过程中形成的冰晶为模板，通过后减压使溶剂升华，再经后处理使其致密化，最终得到仿生结构。该方法具有微观结构可调控性强、原料适用范围广、可制备大尺寸材料等优势，被广泛应用于定向调控陶瓷、聚合物、金属和碳材料等材料的制备领域。探讨冰模板法控制功能纳米材料组装成分级多孔复合材料的影响机制，解析冰模板法与其他材料的加工工艺的互作关系，对改善材料性能和开发新材料具有重要意义。该文阐述了冰模板法制备多尺度复杂仿生结构材料的基本原理、合成策略以及孔隙调控作用，并以冰晶成核和生长为重点，总结了冰模板法对孔道结构进行调控的措施，此外，还介绍了冰模板法辅助构造孔几何形状。最后深入分析了复合材料的微观结构和宏观形貌的相关性，总结了不同冷冻过程对孔道结构的影响机制，并展望了该领域未来的发展方向。

Abstract:

Ice-templating method is also known as directional freezing or freeze-casting. Its principle is to use the ice crystals formed in the freezing process as a template, sublimate the solvent through post decompression, and then densify it through post-treatment, and finally obtain the bionic structure. This method has the advantages of strong controllability of microstructure, wide application range of raw materials, and the ability to prepare large-scale materials, which is widely used in the preparation of directional control ceramics, polymers, metals, and carbon materials. Exploring the impact mechanisms of controlling functional nanomaterials to assemble composite materials by ice-templating method, and analyzing the interaction relationship of ice-templating method with other materials’ processing methodologies, is of great significance for improving material properties and developing new materials. This review describes fundamental principles, synthesis strategies, and pore regulation of the preparation of multi-scale complex bionic structural materials by ice-templating method. Focusing on the nucleation and growth of ice crystals, it summarizes the measures to control the pore structure of ice-templating method. In addition, it outlines the assisted construction of pore geometries by ice-templating method. Finally, the correlation between the microstructure and macromorphology of the composites is analyzed in-depth, highlighting the influence mechanism of different freezing processes on the pore structure, and prospects for future directions in this field.