Chemical versus physical grafting of photoluminescent amino-functional carbon dots onto transparent nematic nanocellulose gels and aerogels
Chemical versus physical grafting of photoluminescent amino-functional carbon dots onto transparent nematic nanocellulose gels and aerogels
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DOI：
10.1007/s10570-019-02619-2
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发表时间：
2019-09
期刊：
影响因子：
5.7
通讯作者：
S. Quraishi;Sven F. Plappert;T. Griesser;W. Gindl-Altmutter;F. Liebner
中科院分区：
文献类型：
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作者：
S. Quraishi;Sven F. Plappert;T. Griesser;W. Gindl-Altmutter;F. Liebner
摘要低折射率的透明基质是光致发光纳米粒子的理想载体，可用于真正的立体三维显示。透明性与高度开放多孔纳米形态的互补使得相应的混合凝胶和气凝胶对于液体和气体检测装置另外具有吸引力。在本文中，我们提出了几乎完全生物基的杂化物，其通过用氨基官能的光致发光碳量子点（CD）装饰来自羧化和个体化纤维素纳米纤维（i-CNF）的高度透明、向列有序的凝胶和气凝胶（15-20 mg cm-3）而获得。后者是通过微波辅助水热柠檬汁。由于将CD锚定到多孔-CNF支架（320 m2 g-1）的大内表面上的方式对混合材料的最终性质（包括CD的浸出和混合物的可重复使用性）具有很大影响，因此本研究评估了物理和化学结合方法的各自优点和缺点。结果证实了共价接枝的优越性。氨基官能化CD的水性碳二亚胺偶联在最终的混合气凝胶中提供了更高的CD产率、明显更高的比表面积值（491 m2 g-1）和略微增强的机械性能，而i-CNF前体醇凝胶的高透光率和纳米形态几乎没有受到损害。因此，我们得出结论，本研究的发光CNF/CD-chem杂化材料是环境友好的化学传感和体积显示应用的有前途的候选者。
AbstractTransparent matrices of low refractive index are promising carriers for photoluminescent nanoparticles targeting true volumetric 3D display applications. Complementation of transparency with a highly open-porous nanomorphology renders respective hybrid gels and aerogels additionally attractive for liquid and gas detection devices. Herein, we present virtually fully bio-based hybrids obtained by decorating highly transparent, nematically ordered gels and aerogels (15–20 mg cm−3) from carboxylated and individualized cellulose nanofibers (i-CNF) with amino-functional photoluminescent carbon dots (CD). The latter were obtained by microwave-assisted hydrothermolysis of lemon juice. As the way of anchoring the CDs onto the large internal surface of the porousi-CNF scaffolds (320 m2g−1) has a great impact on the final properties of the hybrid materials including leaching of CDs and reusability of the hybrid, this study assessed the respective pros and cons of a physical and chemical bonding approach. The results confirmed the superiority of covalent grafting. Aqueous carbodiimide coupling of amino-functionalized CDs afforded higher yields of CDs in the final hybrid aerogels, distinctly higher specific surface values (491 m2g−1) and slightly enhanced mechanical properties while the high light transmittance and nanomorphology of thei-CNF precursor alcogels is virtually not compromised. Therefore, we conclude that the luminescenti-CNF/CD-chem hybrid materials of this study are promising candidates for environmentally friendly chemical sensing and volumetric display applications.Graphic abstract