Cellulose Nanofibers/PEDOT:PSS Conductive Aerogel for Pressure Sensing Prepared by a Facile Freeze-Drying Method

Abstract

The application of flexible wearable pressure sensors in the fields of pressure sensing, electronic skin, and human health monitoring has attracted a lot of attention. Herein, cellulose-nanofiber (CNF)-based aerogels with conducting polymer poly­(3,4-ethylene dioxythiophene)/poly­(styrenesulfonate) (PEDOT:PSS) and glutaraldehyde (GA) as cross-linking agent were designed and prepared by sol–gel cross-linking and freeze-drying. Without any special treatment, these aerogels presented good flexibility and piezoresistive properties. As the analysis of SEM, Raman spectrum, and XPS, the introduction of GA not only improves the mechanical properties of aerogel (the compressive strength at 80% strain has increased from 48 to 66 kPa) but also affects the doping state of PEDOT, which improves the sensitivity of aerogel (from 10.65 to 15.18 kPa–1). In addition, the sensor has been successfully applied to monitor human movements, including not only large movements (joint movements) but also small-scale muscle movements (cheek puffing and articulation recognition). It shows its potential as a widely used green pressure sensor.

Lightweight, flexible, and conductive PEDOT:PSS coated polyimide nanofibrous aerogels for piezoresistive pressure sensor application

“…4c). Compared to uncoated PiNFA, PEDOT:PSS@PI demonstrates notably higher compressive stress at equivalent strains, particularly at 80% strains where this sample can withstand maximum compressive stress values of 250 kPa, which is significantly higher than those reported in previous works 8,27,52,60–62 (Fig. 4d).…”

“…42 For PEDOT:PSS, the minor peaks at 1602, 1039, and 943 cm À1 can be respectively ascribed to the stretching vibration of the benzene ring, SQO, and S-OH in the PSS molecule. 51,52 Moreover, the vibrations observed at 1373 and 1560 cm À1 originated from the C-C or CQC stretching of the quinoidal structure of the thiophene ring. Moreover, the bands at 1265 and 1060 cm À1 are associated with the stretching of the C-O-C bonds in the ethylenedioxy group, while the C-S bonds in the thiophene ring were detected at 993 and 858 cm À1 for the PEDOT of PEDOT:PSS.…”

“…The weight loss observed at temperatures under 100 1C, attributed to water removal, indicates the hydrophilic nature of the PEDOT:PSS compound. 52 In particular, PEDOT:PSS@PI aerogels exhibit four stages of weight loss, including water loss from PEDOT:PSS and three decomposition steps caused by the two constituents. Detailed information about the decomposition of samples can be found in Table S1 (ESI †).…”

Synergy of Organic/Inorganic and Inner/Outer Cooperative Conductive Networks in Polydimethylsiloxane-Based Porous Foam on High-Performance Flexible Sensors

“…To further validate the stability of the cooperative conductive network in the inner and outer layers, the PP@MWCNTs/PDMS sensor exhibited excellent long-term cyclic stability through 5000 cycles of loading and unloading tests under a pressure of 6 kPa (Figure f). Compared with the reported composite foams loaded with conductive fillers in recent years (Table S2), PP@MWCNTs/PDMS exhibited excellent resistive sensitivity and detection range (Figure g). ,,,− …”

Flexible and Wearable Piezoresistive Sensors Based on Double Wrinkled Layers for Motion Monitoring and Human Physiological Signal Monitoring

“…), metal nanomaterials (gold nanoparticles, , silver nanowires, − etc. ), MXene − and conductive polymers − (polypyrrole, polyaniline, polythiophene, PEDOT:PSS, etc.). For example, Cheng et al reported a fiber sensor composed of a conductive electrospun membrane with the micronano three-dimensional (3D) network, which is framed by TPUEM and coated with rGO bridged conductive poly­(styrene- co -methacrylic acid)@ polypyrrole (P­(St-MAA)@PPy) microspheres.…”