Aqueous Dispersion of Carbon Nanomaterials with Cellulose Nanocrystals: An Investigation of Molecular Interactions
Aqueous Dispersion of Carbon Nanomaterials with Cellulose Nanocrystals: An Investigation of Molecular Interactions
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碳纳米材料与纤维素纳米晶体的水分散体：分子相互作用研究
DOI：
10.1002/smll.202202216
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发表时间：
2022-07-28
期刊：
影响因子：
13.3
通讯作者：
Asadi, Amir
中科院分区：
文献类型：
--
作者：
Aramfard, Mohammad;Kaynan, Ozge;Asadi, Amir
将碳纳米材料分散在溶剂中可以有效地将其重要的机械和功能特性转移到聚合物和纳米复合材料中。然而，碳纳米材料的分散性差阻碍了它们在纳米复合材料中的充分潜力。纤维素纳米晶体（CNC）是有前途的分散和稳定的原始碳纳米管（pCNT）和石墨烯纳米片（pGNP）在质子介质中没有功能化。在这里，CNC和pCNT/pGNP之间的分子水平上的潜在机制进行了研究，稳定它们在极性溶剂中的分散体。基于CNC-pCNT/pGNP的光谱学和显微镜表征以及密度泛函理论（DFT）计算，提出了CNC和pCNT/pGNP之间的另外的分子间机理，该机理在CNC的羟基末端基团和pCNT/pGNP的缺陷位点之间形成碳-氧共价键，从而防止在极性溶剂中的再聚集。这项工作的研究结果表明，CNC辅助过程能够在分子水平上利用纳米结构并在更高的长度尺度上定制纳米复合材料的性能。
Dispersing carbon nanomaterials in solvents is effective in transferring their significant mechanical and functional properties to polymers and nanocomposites. However, poor dispersion of carbon nanomaterials impedes exploiting their full potential in nanocomposites. Cellulose nanocrystals (CNCs) are promising for dispersing and stabilizing pristine carbon nanotubes (pCNTs) and graphene nanoplatelets (pGnP) in protic media without functionalization. Here, the underlying mechanisms at the molecular level are investigated between CNC and pCNT/pGnP that stabilize their dispersion in polar solvents. Based on the spectroscopy and microscopy characterization of CNC-pCNT/pGnP and density functional theory (DFT) calculations, an additional intermolecular mechanism is proposed between CNC and pCNT/pGnP that forms carbon-oxygen covalent bonds between hydroxyl end groups of CNCs and the defected sites of pCNTs/pGnPs preventing re-agglomeration in polar solvents. This work's findings indicate that the CNC-assisted process enables new capabilities in harnessing nanostructures at the molecular level and tailoring the performance of nanocomposites at higher length scales.