Highly stable Pd/HNb3O8-based flexible humidity sensor for perdurable wireless wearable applications. Issue 3 (20th January 2021)

• Record Type: Journal Article
• Authors: Lu, Yuyao; Xu, Kaichen; Yang, Min-Quan; Tang, Shin-Yi; Yang, Tzu-Yi; Fujita, Yusuke; Honda, Satoko; Arie, Takayuki; Akita, Seiji; Chueh, Yu-Lun; Takei, Kuniharu
• Is Part Of: Nanoscale horizons. Volume 6:Issue 3(2021)
• Page Start: 260
• Page End: 270
• Publication Date: 2021-01-20
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d0nh00594k
• Languages: English
• ISSNs: 2055-6756

Abstract

Abstract : A Pd/HNb3 O8 flexible humidity sensor is developed with long-term stability at a high humidity level (∼90% RH). Using the sensor, wireless monitoring of human respirations and finger moisture variation under exercise is successfully demonstrated. Abstract : Real-time, daily health monitoring can provide large amounts of patient data, which may greatly improve the likelihood of diagnosing health conditions at an early stage. One potential sensor is a flexible humidity sensor to monitor moisture and humidity information such as dehydration. However, achieving a durable functional nanomaterial-based flexible humidity sensor remains a challenge due to partial desorption of water molecules during the recovery process, especially at high humidities. In this work, we demonstrate a highly stable resistive-type Pd/HNb3 O8 humidity sensor, which exhibits a perdurable performance for over 100 h of cycle tests under a 90% relative humidity (RH) without significant performance degradation. One notable advantage of the Pd/HNb3 O8 humidity sensor is its ability to regulate hydroniums due to the strong reducibility of H atoms dissociated on the Pd surface. This feature realizes a high stability even at a high humidity (99.9% RH). Using this superior performance, the Pd/HNb3 O8 humidity sensor realizes wireless monitoring of the changes in the fingertip humidity of an adult under different physiological states, demonstrating a facile and reliable path for dehydration diagnosis.