Ma Haoren, Liu Sijia, Ren Jinyi, Liu Xiaochan, Zhang Weiyi, Zhu Ying, Yuan Zhipeng, Zhu Jinxu, Yi Xibin
Shandong Key Laboratory of Advanced Glass Manufacturing and Technology, Advanced Materials Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China.
Gels. 2025 Jun 9;11(6):440. doi: 10.3390/gels11060440.
Traditional β-eucryptite (LiAlSiO) is renowned for its unique characteristics of low thermal expansion and high temperature thermal stability, making it an ideal material for precision instruments and aerospace applications. In this study, β-eucryptite was fabricated into an aerogel structure through the sol-gel process and supercritical drying method and using alumina sol as a cost-effective precursor. The synthesized β-eucryptite aerogel demonstrated unique properties including a negative thermal expansion coefficient (-7.85 × 10 K), low density (0.60 g/cm), and high specific surface area (18.1 m/g). X-ray diffraction (XRD) and transmission electron microscopy (TEM) mutually corroborated the crystalline structure of β-eucryptite, with XRD confirming the phase purity and TEM imaging revealing well-defined crystal lattice characteristics. Combined nitrogen adsorption-desorption analysis and scanning electron microscopy observations supported the hierarchical porous microstructure, with SEM visualizing interconnected nanoporous networks and nitrogen sorption data verifying the porosity. The negative thermal expansion behavior was directly linked to the β-eucryptite crystal structure, as collectively validated by thermal expansion measurements. Additionally, Fourier transform infrared spectroscopy (FTIR) independently confirmed the aluminosilicate framework structure through characteristic vibrational modes. This research shows the innovation in the synthesis of β-eucryptite aerogel, especially its application potential in precision instruments and building materials that need low thermal expansion and high stability, and the use of aluminum sol as an aluminum source has simplified the preparation steps and reduced production costs.
传统的β-锂霞石（LiAlSiO）以其低热膨胀和高温热稳定性的独特特性而闻名，使其成为精密仪器和航空航天应用的理想材料。在本研究中，通过溶胶-凝胶法和超临界干燥法，以氧化铝溶胶作为经济高效的前驱体，将β-锂霞石制成气凝胶结构。合成的β-锂霞石气凝胶表现出独特的性能，包括负热膨胀系数（-7.85×10 K）、低密度（0.60 g/cm）和高比表面积（18.1 m/g）。X射线衍射（XRD）和透射电子显微镜（TEM）相互证实了β-锂霞石的晶体结构，XRD确认了相纯度，TEM成像揭示了明确的晶格特征。联合氮吸附-脱附分析和扫描电子显微镜观察支持了分级多孔微观结构，SEM可视化了相互连接的纳米多孔网络，氮吸附数据验证了孔隙率。负热膨胀行为直接与β-锂霞石晶体结构相关，热膨胀测量共同验证了这一点。此外，傅里叶变换红外光谱（FTIR）通过特征振动模式独立确认了硅铝酸盐骨架结构。本研究展示了β-锂霞石气凝胶合成方面的创新，特别是其在需要低热膨胀和高稳定性的精密仪器和建筑材料中的应用潜力，并且使用铝溶胶作为铝源简化了制备步骤并降低了生产成本。
