Carbon Nanotube/Chitosan-Based Elastic Carbon Aerogel for Pressure Sensing

Abstract

Elastic carbon materials with high compressibility are ideal candidates for flexible piezoresistive sensors. Carbon nanotubes (CNTs) are promising nanoblocks for fabricating compressible and elastic carbon aerogels because of their excellent conductivity and mechanical strength. However, insufficient interaction among CNTs makes them difficult to assemble in an elastic macrostructure. Herein, a facile yet effective method was proposed to fabricate a compressible and elastic carbon aerogel from multiwalled carbon nanotubes (MWCNTs) using chitosan as a binder. The biopolymer can link MWCNTs into continuous lamellas and lead to three-dimensional architectures with excellent structural stability. The carbon aerogel can withstand a high compression strain (90%) and exhibits excellent fatigue resistance, with only 8% plastic deformation after 50 000 cycles at 50% strain. It also shows a high resistance stability after 50 000 compression cycles and good sensitivity (4.45 kPa–1) and can detect human biological signals. Satisfactory mechanical and sensing properties enable its application in wearable piezoresistive sensors.

Chemistry of Chitosan Aerogels: Three‐Dimensional Pore Control for Tailored Applications

“…Table S5 summarizes the literature on carbon aerogels derived from chitosan. These materials generally have microporous structures with high specific surface areas up to % 2500 m 2 g À1 , [233,234] depending on the gel preparation conditions,c alcination temperature,a nd KOHa nd/or K 2 CO 3 activation procedure.S ome applications of carbon aerogels have been proposed taking advantage of their high surface area, Nc ontent, and electrical conductivity as adsorbents (Section 5.5.1), [233][234][235] sensors, [236] and supercapacitors, [237,238] sometimes in combination with electrically conductive carbon nanotubes. [236]…”

Recent Advances in Natural Functional Biopolymers and Their Applications of Electronic Skins and Flexible Strain Sensors

“…These results showed that the fabrication of “green” sensor reduced the energy consumption for wearable monitoring. Except as mentioned above, other materials such as CNTs, carbon black (CB), conductive polymers, and graphene are used in combined with chitosan to fabricate the flexible strain sensors [ 88 , 89 , 90 , 91 , 92 ]. For examples, CS/CB nanocomposite sponges were fabricated via combining solution-mixing and freeze-drying methods, which presented sensitive strain sensing performance [ 88 ].…”

“…Carbon materials with good conductivity, high elasticity and extensibility are suitable candidates for flexible sensors. Luo et al have proposed a simple and effective method to build a compressible carbon aerogel from multiwalled CNTs by employing CB as a binder [ 89 ]. CB can link multiwalled CNTs into continuous lamellas and result in stable 3D structures.…”

Chemie der Chitosan‐Aerogele: Lenkung der dreidimensionalen Poren für maßgeschneiderte Anwendungen

“…Die Materialien haben im Allgemeinen mikroporçse Strukturen mit großen spezifischen Oberflächen von bis zu 2500 m 2 g À1 , [233,234] abhängig von den Herstellungsbedingungen des Gels,d en Kalzinierungstemperaturen sowie KOH-und/oder K 2 CO 3 -Aktivierungsverfahren. Einige Anwendungen wurden vorgeschlagen, welche die große Oberfläche,d en N-Gehalt und die elektrische Leitfähigkeit nutzen:A dsorptionsmittel (Abschnitt 5.5.1), [233][234][235] Sensoren [236] und Superkondensatoren, [237,238] manchmal kombiniert mit elektrisch leitfähigen Kohlenstoffnanorçhren. [236]…”

“…Einige Anwendungen wurden vorgeschlagen, welche die große Oberfläche,d en N-Gehalt und die elektrische Leitfähigkeit nutzen:A dsorptionsmittel (Abschnitt 5.5.1), [233][234][235] Sensoren [236] und Superkondensatoren, [237,238] manchmal kombiniert mit elektrisch leitfähigen Kohlenstoffnanorçhren. [236]…”