Molecular‐Level Contact of Graphene/Silver Nanowires through Simultaneous Dispersion for a Highly Stable Wearable Electrothermal Heater

Abstract

Silver nanowires (AgNWs) with low sheet resistances are excellent potential candidates for high‐performance wearable electrothermal heaters operated through Joule heating. However, the thermal oxidation and electrical instability of AgNWs caused by high contact resistance and poor adhesion to different substrates considerably limit their use in devices. Graphene is used in a AgNW/graphene hybrid owing to its low oxygen permeability, lower contact resistance with AgNWs, and good van der Waals interactions. Molecular‐level contacts between AgNWs and graphene must be achieved to maximize the synergy of these properties. In this study, a multifunctional polymer possessing styrene sulfonate‐based copolymer and disulfide groups is designed; these groups allow the simultaneous dispersion of AgNWs and graphene in an aqueous solution through self‐assembly. Since this polymer promotes molecular‐level contact between AgNWs and graphene, the oxidation and Joule‐heating stabilities of the hybrid dramatically increase. In addition, a freestanding AgNW/graphene film is readily prepared, exhibiting good attachable properties on various substrates and superior stability under harsh conditions (85 °C and 85% relative humidity for 7 days). The AgNW/graphene hybrid film displays a low sheet resistance (0.36 ± 0.02 Ω sq−1) with good performance as a high‐performance electrothermal heater (200 °C at 1.5 V).

Design of Highly Conductive Leather Based on Zirconium Ion Coordination for Health Protection in Severe Harsh Conditions

“…The cold climate has increased the difficulty and risk of outdoor work, driving the development and progress of heaters. [28] The experiment uses a DC power supply to make CNTs@Zr@OTL generate the Joule heating effect, increase the temperature of the surface and the surrounding environment, and apply it to daily use scenarios in complex environments. Figure S5 (Supporting Information) is an infrared thermography image of the Joule heating temperature change of CNTs@Zr@OTL under a 20 V external DC power supply.…”

One-Step Method for Fabricating Janus Aramid Nanofiber/MXene Nanocomposite Films with Improved Joule Heating and Thermal Camouflage Properties

“…According to the Joule effect, electrothermal composites can generate heat when an electric current is passed through them. Conductive fillers commonly include metal materials (e.g., Ag), , carbon-based materials (e.g., carbon nanotubes), conductive polymers (e.g., polypyrene and polyaniline), , and two-dimensional materials (e.g., graphene). − Metallic materials are prone to oxidation and have high densities, while conductive polymers generally exhibit relatively poor thermal stability and conductivity. Graphene, as a two-dimensional material, typically requires substantial driving voltage for its operation, limiting practical applications …”