Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Institute of Molecular Functional Materials, State Key Laboratory of Nanoscience, Division of Biomedical Engineering and Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, HKUST-Shenzhen Research Institute, Shenzhen, 518057, China.
Adv Mater. 2017 Dec;29(46). doi: 10.1002/adma.201703900. Epub 2017 Oct 16.
Building humidity sensors possessing the features of diverse-configuration compatibility, and capability of measurement of spatial and temporal humidity gradients is of great interest for highly integrated electronics and wearable monitoring systems. Herein, a visual sensing approach based on fluorescent imaging is presented, by assembling aggregation-induced-emission (AIE)-active molecular rotors into a moisture-captured network; the resulting AIE humidity sensors are compatible with diverse applications, having tunable geometries and desirable architectures. The invisible information of relative humidity (RH) is transformed into different fluorescence colors that enable direct observation by the naked eyes based on the twisted intramolecular charge-transfer effect of the AIE-active molecular rotors. The resulting AIE humidity sensors show excellent performance in terms of good sensitivity, precise quantitative measurement, high spatial-temporal resolution, and fast response/recovery time. Their multiscale applications, such as regional environmental RH detection, internal humidity mapping, and sensitive human-body humidity sensing are demonstrated. The proposed humidity visualization strategy may provide a new insight to develop humidity sensors for various applications.
构建具有多种配置兼容性和空间及时间湿度梯度测量能力的湿度传感器，对于高度集成的电子设备和可穿戴监测系统而言具有重要意义。在此，提出了一种基于荧光成像的可视化传感方法，即将聚集诱导发射（AIE）活性分子转子组装成一个湿度捕获网络；由此得到的 AIE 湿度传感器可兼容多种应用，具有可调的几何形状和理想的结构。相对湿度（RH）的不可见信息被转化为不同的荧光颜色，通过 AIE 活性分子转子的扭曲分子内电荷转移效应，可实现肉眼直接观察。所得到的 AIE 湿度传感器在灵敏度、精确的定量测量、高时空分辨率以及快速响应/恢复时间方面表现出优异的性能。其多尺度应用，如区域环境 RH 检测、内部湿度映射和敏感人体湿度感应等，也得到了验证。所提出的湿度可视化策略可能为开发各种应用的湿度传感器提供新的思路。
