Multifunctional Flexible Humidity Sensor Systems Towards Noncontact Wearable Electronics

Lu, Yiji; Yang, Geng; Shen, Yajing; Yang, Huayong; Xu, Kaichen

doi:10.1007/s40820-022-00895-5

Cited by 114 publications

(66 citation statements)

References 188 publications

(268 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The requirements for materials that make them suitable for moisture measurement, and consequently, for use in humidity sensors, were listed by Kamekichi and Tatsumi [2], and are, primarily, high sensitivity, fast response time, long-term durability, reproducibility, low cost, low hysteresis loop and operation over a wide range of RH and temperatures. To date, several types of humidity sensors have been developed [3][4][5][6][7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Polyantimonic acid-based materials evaluated as moisture sensors at ambient temperature

Mendes

Kurapova

Faia

et al. 2022

J Solid State Electrochem

View full text Add to dashboard Cite

Humidity sensors are in high demand for many applications, such as environmental monitoring and air and food quality control. Despite many inorganic and organic materials exhibit moisture sensing properties, the electrical response of many existing sensors is not stable along the time. Polyantimonic acid (PAA) is characterized by elevated proton conductivity and by high thermal stability: consequently, it is seen as promising proton conductor for usage in humidity sensing devices. In this work, for the first time, PAA-based bulk solid membranes were produced and tested as potential materials for relative humidity (RH) detection and their moisture sensitivity was evaluated. Two different amounts of binder were used for moulding the solid sensors: the ones with 10% of binder were designated as 90PAA, while the ones with 20% were named 80PAA. The structures of the solid samples were investigated by X-ray diffraction (XRD) technique, adsorption–desorption curves via Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) techniques. The electrical behaviour was examined at ambient temperature by electrical impedance spectroscopy in the entire relative humidity (RH) interval (0–100%) and in the frequency range of 40 Hz up to 60 MHz. Electrical response of the materials was correlated with the structural features of the membranes. Both 90PAA and 80PAA sensors showed total resistance 3 × 105 and 3.5 × 105 Ω at 10% RH, respectively. A linear decrease of the resistance on RH was observed in the range 30–90% RH for both sensors. The electrical response of the evaluated PAA-based sensors displays good repeatability and reproducibility: the ones with lower binder content showed higher moisture sensitivity as well as very good time stability over 1 year.

show abstract

Section: Introductionmentioning

confidence: 99%

Polyantimonic acid-based materials evaluated as moisture sensors at ambient temperature

Mendes

Kurapova

Faia

et al. 2022

J Solid State Electrochem

View full text Add to dashboard Cite

show abstract

“…Accordingly, the change in frequency can be expressed as follows [ 39 ]:

where f r represents the resonant frequency, C is a constant,

m is the mass change caused by the absorption of water, and A denotes the sensing area. Although SAW humidity sensors have the advantages of high sensitivity, a miniaturized structure, stable frequency, and low power consumption [ 40 ], they are typically fabricated on rigid substrates [ 41 ], showing poor compatibility with flexible electronics.…”

Section: Flexible Sensors For Sensing Humiditymentioning

confidence: 99%

An Overview of Flexible Sensors: Development, Application, and Challenges

Liu

Zhang

et al. 2023

Sensors

View full text Add to dashboard Cite

The emergence and advancement of flexible electronics have great potential to lead development trends in many fields, such as “smart electronic skin” and wearable electronics. By acting as intermediates to detect a variety of external stimuli or physiological parameters, flexible sensors are regarded as a core component of flexible electronic systems and have been extensively studied. Unlike conventional rigid sensors requiring costly instruments and complicated fabrication processes, flexible sensors can be manufactured by simple procedures with excellent production efficiency, reliable output performance, and superior adaptability to the irregular surface of the surroundings where they are applied. Here, recent studies on flexible sensors for sensing humidity and strain/pressure are outlined, emphasizing their sensory materials, working mechanisms, structures, fabrication methods, and particular applications. Furthermore, a conclusion, including future perspectives and a short overview of the market share in this field, is given for further advancing this field of research.

show abstract

“…187 In addition, hybrid nanofilms can be utilized to prepare breathable skin-mountable humidity sensors. [215][216][217] For instance, a breathable humidity sensor composed of cellulose nanocrystal/iron(III) ion/PVA (CNC/Fe 3+ /PVA) hybrid film was fabricated. Due to the porous structure of the CNC/Fe 3+ /PVA film, the sensor showed excellent permeability (3.03 kg m −2 d −1 ).…”

Section: Humidity and Hydration Sensorsmentioning

confidence: 99%