A Nanofibrillated Cellulose-Based Electrothermal Aerogel Constructed with Carbon Nanotubes and Graphene

Abstract

Nanofibrillated cellulose (NFC) as an environmentally friendly substrate material has superiority for flexible electrothermal composite, while there is currently no research on porous NFC based electrothermal aerogel. Therefore, this work used NFC as a skeleton, combined with multi-walled carbon nanotubes (MWCNTs) and graphene (GP), to prepare NFC/MWCNTs/GP aerogel (CCGA) via a simple and economic freeze-drying method. The electrothermal CCGA was finally assembled after connecting CCGA with electrodes. The results show that when the concentration of the NFC/MWCNTs/GP suspension was 5 mg mL−1 and NFC amount was 80 wt.%, the maximum steady-state temperature rise of electrothermal CCGA at 3000 W m−2 and 2000 W m−2 was of about 62.0 °C and 40.4 °C, respectively. The resistance change rate of the CCGA was nearly 15% at the concentration of 7 mg mL−1 under the power density of 2000 W m−2. The formed three-dimensional porous structure is conducive to the heat exchange. Consequently, the electrothermal CCGA can be used as a potential lightweight substrate for efficient electrothermal devices.

Research Progress on the Preparation of Flexible and Green Cellulose-Based Electrothermal Composites for Joule Heating Applications

“…The MWCNTs/GP/CNFs mixture was ultrasonically dispersed and poured into Petri dishes. The cellulose-based electrothermal aerogels were prepared by freezing the MWCNTs/GP/CNFs mixture at −50 °C for 2 h and vacuum freeze-dried for 48 h . The controllable Joule heating performance and long-term heating stability of cellulose-based aerogels were studied using size, structure, and performance regulation. , Mixed solutions of an MXene and CNFs were poured into a mold with a certain thickness and then freeze-dried to obtain a controlled size and structure (Figure a–d).…”

A Review of Graphene-Based Materials/Polymer Composite Aerogels

“…However, the enhanced dielectric constants were always at the expense of similar increases in loss, which was attributed to the motion of free charge carriers resulting from the formation of continuous conductive networks. Due to excellent electrical conductivity and thermal conductivity, graphene aerogel can be composited into the polymer matrix as a functional filler, thereby achieving application value in electrothermal field [111]. Yang et al [112] reported graphene aerogel/epoxy resin nanocomposites (EGAC) with excellent electrothermal properties.…”

Recent Advances in the Synthesis and Application of Three-Dimensional Graphene-Based Aerogels

“…The dispersion of graphene in substrate is always particularly important for improving the performance of aerogel. In order to avoid aggregation induced by strong a van der Waals force, many preparation methods involving covalent and/or non-covalent modification between GO and polymer matrix and appropriate ultrasonic dispersion are employed [ 33 ]. The dispersion of graphene can be reflected on the morphology of aerogel characterized by SEM, SEM-EDS and TEM, and the XRD pattern.…”