Vapor sensing with color-tunable multilayered coatings of cellulose nanocrystals
Vapor sensing with color-tunable multilayered coatings of cellulose nanocrystals
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具有颜色可调的纤维素纳米晶体多层涂层的蒸汽传感
DOI：
10.1016/j.carbpol.2017.06.059
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发表时间：
2017
影响因子：
11.2
通讯作者：
Chang Yu
中科院分区：
文献类型：
--
作者：
Zhao Yu;Gao Guizhi;Liu Dagang;Tian Donglin;Zhu Yinyan;Chang Yu
胶体纤维素纳米晶体被LBL沉积以形成牢固堆叠的光学涂层，其中纳米棒调节其头对尾的结合并在轴向离心方向上排列。反射颜色从蓝色到橙子的周期性转变可经由沉积层调整来调谐。当敏感涂层分别暴露于NH3·H2O、H2O、HCl和HAc蒸气中时，响应过程中的颜色变化在室温下是不可逆的，并且高度依赖于蒸气扩散和化学界面相互作用。因此，在室温下，HAc蒸气呈现出最长的波长感测跃迁，而碱性NH3·H2O显示出比HAc和H2O更小的恢复率。在50 °C加热条件下，除盐酸腐蚀后的膜层外，其余敏感膜层均能恢复到原始状态。因此，通过纳米纤维素的蒸汽的肉眼定性检测可以通过颜色偏移的发散来实现，这在化学传感器中是非常重要的。
Colloidal cellulose nanocrystals were LBL deposited to form firmly-stacked optical coatings in which the nanorods regulated their head-to-tail association and aligned in the axial-centrifuged direction. The periodically transition from blue to orange of reflected colors was tunable via deposition layer adjustment. While the sensing coating was exposed to vapors of NH3.H2O, H2O, HCl and HAc, respectively, the color variation in the response process was irreversible at room temperature and highly dependent on vapor diffusion and chemical interface interaction. Consequently, HAc vapor presented the longest sensing transition of wavelength, whereas the alkaline NH3.H2O displays a less recovery ratio than HAc and H2O at room temperature. Under heating at 50 °C, the sensed coatings could mostly be restored to their original state except HCl-etched one. Therefore, the naked-eyed qualitative detectability of vapors by nanocellulose could be realized by the divergence in color shift which is of great importance in chemical sensors.