Printable and Flexible Humidity Sensor Based on Graphene -Oxide-Supported MoTe2 Nanosheets for Multifunctional Applications

Abstract

This study focuses on a novel humidity sensor composed of graphene-oxide (GO)-supported MoTe2 nanosheets. Conductive Ag electrodes were formed on PET substrates by inkjet printing. A thin film of GO-MoTe2 was deposited on the Ag electrode used for adsorbing humidity. The experiment’s results demonstrate that MoTe2 are attached to GO nanosheets uniformly and tightly. The capacitive output of the sensors with various ratios of GO/MoTe2 has been tested for different levels of humidity (11.3–97.3%RH) at room temperature (25 °C). As a consequence, the obtained hybrid film exhibits superior sensitivity (94.12 pF/%RH). The structural integrity and interaction of different components were discussed to afford the prominent humidity sensitivity performance. Under the bending condition, the output curve of the sensor has no obvious fluctuation. This work provides a low-cost way to build flexible humidity sensors with high-performance in environmental monitoring and healthcare.

Flexible Humidity Sensor Based on a Graphene Oxide–Carbon Nanotube-Modified Co3O4 Nanoparticle-Embedded Laser-Induced Graphene Electrode

“…Possible Humidity Sensing Mechanism. The sensing mechanism underlying resistive humidity sensors has been investigated, 2,15 revealing a distinctive two-stage process (Figures 5a and S12). Under conditions of low humidity, a limited quantity of water molecules within the ambient air adhere to the surface of the GO−MWCNT humidity-sensitive layer, transforming into H 3 O + and OH − ions through ionization.…”

“…Humidity sensors employ various working mechanisms and are capable of generating multiple physical signals. With respect to distinct measurement techniques, humidity sensors can be classified into a range of types, including resistive, − capacitive, − impedance, , and voltage. , Traditional humidity sensors are predominantly constructed on rigid substrates, resulting in limited comfort during use and inability to adapt to surfaces with complex geometries. , The emergence of flexible and soft electronic technology in recent years has revolutionized the wearable applications, giving rise to flexible humidity sensors that cater to novel requirements like breath monitoring …”