Abstract:
Wearable humidity sensors are attracting strong attention as they allow for real-time and continuous monitoring of important physiological information by enabling activity tracking as well as air quality assessment. Amongst 2Dimensional (2D) materials, graphene oxide (GO) is very attractive for humidity sensing due to its tuneable surface chemistry, high surface area, processability in water, and easy integration onto flexible substrates. However, strong hysteresis, low sensitivity, and cross-sensitivity issues limit the use of GO in practical applications, where continuous monitoring is preferred. Herein, a wearable and wireless impedance-based humidity sensor made with pyrene-functionalized hexagonal boron nitride (h-BN) nanosheets is demonstrated. The device shows enhanced sensitivity towards relative humidity (RH) (>1010 Ohms/%RH in the range from 5% to 100% RH), fast response (0.1 ms), no appreciable hysteresis, and no cross-sensitivity with temperature in the range of 25-60 °C. The h-BN-based sensor is able to monitor the whole breathing cycle process of exhaling and inhaling, hence enabling to record in real-time the subtlest changes of respiratory signals associated with different daily activities as well as various symptoms of flu, without requiring any direct contact with the individual.
摘要:
可穿戴湿度传感器吸引了人们的注意力,因为它们可以通过进行活动跟踪和空气质量评估来实时监测重要的生理信息。在二维(2D)材料中,氧化石墨烯(GO)由于其可调节的表面化学而对湿度传感非常有吸引力,高表面积,在水中的可加工性和易于集成到柔性基材上。然而,大滞后,低灵敏度和强交叉灵敏度的问题限制了GO在实际应用中的使用,连续监测是首选。在这里,我们展示了一个可穿戴和无线阻抗为基础的湿度传感器与芘功能化的六方氮化硼(h-BN)纳米片,这表明对相对湿度的敏感性增强,RH(>1010欧姆/%RH,范围从5%到100%RH),快速响应(0.1ms),在25-60°C的范围内没有明显的滞后和交叉敏感性。我们最后证明了基于h-BN的传感器能够监测呼气和吸气的整个呼吸周期过程,因此能够实时记录与不同日常活动相关的呼吸信号的细微变化以及流感的各种症状,不需要与个人直接接触。本文受版权保护。保留所有权利。