Nanoporous Carbon Aerogels for Laser-Printed Wearable Sensors

Abstract

Laser-induced porous carbon materials have received growing attention as electrodes in micro-supercapacitors, electronics, and biosensors. Herein, resorcinol-formaldehyde (RF) aerogel is used for laser carbonization and activation to produce a nanoporous black conductive surface with high porosity and a specific surface area of 703 m 2 •g −1 as well as high absorbance to infrared light (∼98%). Furthermore, inspired by the photoreception behavior of octopus arms, a "thunder motif" nanoporous carbon aerogel-based resistance-type sensor is able to be laserprinted on paper-reinforced RF aerogel, which shows high integration of temperature (0.19%•°C −1 ), strain (gauge factor 16.7), humidity, and especially infrared light (0.12%•mW −1 , which is not common for a normal on-skin sensor) sensing in one device and better performance than a serpentine layout sensor. With its good flexibility and biodegradability, this multifunctional sensor can serve as an on-skin wearable sensor that can sense gesture changes and breathing.

Optimizing the performance of the near-infrared (NIR) photothermal conversion via modulating the domain size of the chiral nematic phase in co-assembled cellulose nanocrystal composite films

“…19,41 In the CP 5 composite film, the relative resistance changes (R/R 0 ) showed linearity in a wide range between 20 and 100 1C and the maximum TCR reached À1.285%1C À1 , giving an ultrahigh sensitivity in wide temperature changes, superior to other temperature-sensing materials based on the photothermal conversion process reported in the literature (Table 1). 19,[42][43][44][45][46][47][48][49] Furthermore, the relative resistance change of the CP 5 film was recorded repeatedly through alternatively ON/OFF NIR light irradiation (Fig. 4(b)).…”

Biocompatible Material‐Based Flexible Biosensors: From Materials Design to Wearable/Implantable Devices and Integrated Sensing Systems

“…Compared with hydrogels, aerogels show lower density and high porosity, which improves their maneuverability and allows them to serve as fillers. [168] Wang et al [169] filled the spacer fabric with graphene-based aerogel to create a composite fabric with a 3D structure. The composite's resistance decreased as the temperature rose, exhibiting NTC behavior and having a highly linear thermal response between 32 and 114 °C (Figure 17g).…”

“…Compared with hydrogels, aerogels show lower density and high porosity, which improves their maneuverability and allows them to serve as fillers. [ 168 ] Wang et al. [ 169 ] filled the spacer fabric with graphene‐based aerogel to create a composite fabric with a 3D structure.…”

Revolution in Flexible Wearable Electronics for Temperature and Pressure Monitoring—A Review

“…The biomedical research community has recently shown a lot of interest in printed wearable sensing apparatuses for surveillance key bio-signals such as body temperature, respiration rate, blood pressure, glucose, and electrophysiology [56][57][58]. These sensing apparatuses are built on biocompatible substrates and adhere to the target surfaces in a conformable manner.…”