School of Electronics and Information Engineering, Hebei University of Technology, 5340 Xiping Road, Tianjin 300401, PR China.
State Key Laboratory of Reliability and Intelligence Electrical Equipment, Hebei University of Technology, Tianjin 300130, PR China; National Engineering Research Center for Technological Innovation Method and Tool, and School of Mechanical Engineering, Hebei University of Technology, Tianjin 300401, PR China.
J Colloid Interface Sci. 2022 Feb;607(Pt 2):2010-2018. doi: 10.1016/j.jcis.2021.09.189. Epub 2021 Oct 12.
The development of high-performance humidity sensors is of great significance to explore their practical applications in the fields of environment, energy saving and safety monitoring. Herein, a flexible, non-contact and multifunctional humidity sensor based on two-dimensional Co-metal organic frameworks (Co-MOF) nanosheets is proposed, which is fabricated by simple bottom-up synthesis method. Furthermore, environmentally friendly, renewable and abundant biomass phytic acid (PA) is modified on the surface of Co-MOF nanosheets, which releases free protons being capable of etching the framework of MOF to improve the hydrophilicity and conductivity of MOF. Compared with Co-MOF-based sensor, the Co-MOF@PA-based sensor exhibits significantly enhanced sensitivity and broadened response range within 23-95% relative humidity (RH). The humidity sensor has an excellent humidity sensing response over 2 × 10. The Co-MOF@PA-based sensor shows good flexibility and humidity sensing properties, endowing it with multifunctional applications in real-time facial respiration monitoring, skin humidity perception, cosmetic moisturizing evaluation and fruit freshness testing. Four respiration patterns, including slow breath, deep breath, normal breath and fast breath are wirelessly monitored in real time by Co-MOF@PA-based sensor and recorded by mobile phone software. The research work presents potential applications in human-machine interactions (HMI) devices in future.
高性能湿度传感器的发展对于探索其在环境、节能和安全监测等领域的实际应用具有重要意义。本文提出了一种基于二维钴金属有机骨架（Co-MOF）纳米片的灵活、非接触和多功能湿度传感器，该传感器通过简单的自下而上合成方法制备。此外，在 Co-MOF 纳米片表面修饰了环保、可再生且丰富的生物质植酸（PA），它能够释放游离质子来刻蚀 MOF 的骨架，从而提高 MOF 的亲水性和导电性。与基于 Co-MOF 的传感器相比，基于 Co-MOF@PA 的传感器在 23%至 95%相对湿度（RH）范围内表现出显著增强的灵敏度和更宽的响应范围。湿度传感器在 2×10^5 以上具有出色的湿度传感响应。Co-MOF@PA 基传感器具有良好的柔韧性和湿度传感性能，使其在实时面部呼吸监测、皮肤湿度感知、化妆品保湿评价和水果新鲜度测试等多功能应用中具有潜力。通过 Co-MOF@PA 基传感器可以实时无线监测包括缓慢呼吸、深呼吸、正常呼吸和快速呼吸在内的四种呼吸模式，并通过手机软件进行记录。该研究工作为未来人机交互（HMI）设备中的应用提供了新的思路。
