Nonfreeze-Drying Approach for Anisotropic Compression-Resilient Inorganic Aerogels by Guided Self-Assembly and Controlled Mineralization of Bacterial Cellulose
Nonfreeze-Drying Approach for Anisotropic Compression-Resilient Inorganic Aerogels by Guided Self-Assembly and Controlled Mineralization of Bacterial Cellulose
复制标题
通过细菌纤维素的引导自组装和受控矿化实现各向异性压缩弹性无机气凝胶的非冷冻干燥方法
DOI：
10.1021/acssuschemeng.9b02195
复制
发表时间：
2019-09-03
影响因子：
8.4
通讯作者：
Xu, Yan
中科院分区：
文献类型：
--
作者：
Li, Guannan;Zou, Chen;Xu, Yan
工业部门和科学界对气凝胶的兴趣日益增加，这引发了持续的努力，以开发用于更广泛应用的气凝胶的合理组织的方法。在这里，我们表明，各向异性压缩弹性纤维素/二氧化硅气凝胶与可定制的大孔可以实现通过引导自组装和控制矿化的细菌纤维素。纤维素/二氧化硅气凝胶复制了改性细菌纤维素的介观结构特征，其具有在使用聚苯乙烯球的生物合成期间定制的大孔。在十六烷基三甲基溴化铵存在下，通过调节四丙氧基硅烷的水解和缩聚来控制细菌纤维素纳米纤维周围的二氧化硅沉积。在60%压缩应变下，纤维素/二氧化硅经受100次循环，沿生长方向沿着具有几乎100%的高度恢复，并且经受1次循环，垂直于生长方向具有86.2%的高度恢复。各向异性的压缩回弹性归因于涉及二氧化硅纳米颗粒尺寸、串珠状纳米结构和具有蜂窝孔的波状纤维的取向介观结构的多尺度变形。说明了纤维素/二氧化硅气凝胶用于含油水清洁的潜力。我们的工作通过体内介观结构工程和受控矿化为细菌纤维素基先进材料开辟了新的可能性。
Increasing interest in aerogels among industrial sectors and the scientific community has sparked a sustained effort to develop methodologies for rational organization of aerogels for broader applications. Here we demonstrate that anisotropically compression-resilient cellulose/silica aerogels with tailorable macropores can be realized through guided self-assembly and controlled mineralization of bacterial cellulose. The cellulose/silica aerogels replicate the mesostructural features of modified bacterial cellulose with the macropores tailored during the biosynthesis using polystyrene spheres. Silica deposition surrounding bacterial cellulose nanofibers is controlled by moderating the hydrolysis and polycondensation of tetrapropoxysilane in the presence of cetyltrimethylammonium bromide. Cellulose/silica withstands 100 cycles with almost 100% height recovery along the growth direction and 1 cycle with 86.2% height recovery perpendicular to the growth direction at 60% compression strain. The anisotropic compression resilience is attributed to a multiscale deformation involving silica nanoparticles size, bead-on-string nanostructure, and oriented mesostructure of wavy fibers with cellular pores. The potential of the cellulose/silica aerogels for oily water cleansing is illustrated. Our work opens up new possibilities for bacterial cellulose-based advanced materials through in vivo mesostructure engineering and controlled mineralization.