Superior Stable, Highly Efficient, and Anisotropic Electrothermal Composite Heater in Various Directions with Fast Response Based on Aligned Carbon Nanotube Sheets

Abstract

Flexible electrothermal heaters have a great potential for applications of warm‐keeping and thermotherapy. However, those common electrothermal heaters are so sensitive to strain that they are hard to resistant to deformation while still keeping the stable and outstanding electrothermal performance. Here, a flexible and elastic composite heater with a stable electrothermal property under varied strain with large deformation is developed by mimicking the wrinkle feature of human skin in a carbon nanotube (CNT)/polydimethylsiloxane (PDMS) bilayered structure. The created wrinkle feature of CNT film from the resilience of PDMS makes the electrothermal heater a stable electrothermal performance within 30–40% strain in different directions. The aligned preference of CNTs in the CNT film gives the electrothermal heater an ability that shows different electrothermal performance depending on different angles between the direction of CNT alignment and the long axis of the sample. This composite electrothermal heater also presents a highly efficient electrothermal performance that can reach 200 °C within 30s upon 2 V.

Fully Handwritten Flexible Electrothermal Devices Using a Whiteboard Marker Pen with Carbon Nanoparticle Ink

“…Thermal performance is an important indicator for evaluating the performance of devices, 1 which can be reflected by thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) curves in Figure 1f. To study the thermal performance of electrothermal devices, it is necessary to conduct a TGA test of the prepared carbon conductive ink, which consists of a functional layer of electrothermal films and ETAs.…”

“…Electrothermal devices including electrothermal films and electrothermal actuators (ETAs) are expected to have great potential in fields like home heating 1,2 and thermotherapy 3 due to the merits of simplicity, low cost, and fast production. Besides, these heating systems also display their potential in drug delivery, 4 thermochromic displays, 5 and wearable thermotherapy.…”

“…Electrothermal devices including electrothermal films and electrothermal actuators (ETAs) are expected to have great potential in fields like home heating , and thermotherapy due to the merits of simplicity, low cost, and fast production. Besides, these heating systems also display their potential in drug delivery, thermochromic displays, and wearable thermotherapy. , Electrothermal films, which are operated by the Joule heating effect, can convert part of electrical energy into heat and deliver it to surroundings through heat conduction and radiation. , As its heating effect largely depends on functional heating materials and flexible substrates, the performance can be improved by adjusting the aforementioned two aspects and their interaction. ,,, …”

Highly Responsive Soft Electrothermal Actuator with High-Output Force Based on Polydimethylsiloxane (PDMS)-Coated Carbon Nanotube (CNT) Sponge

“…Soft actuators, composed of flexible components that provide multiple degrees of freedom, undergo mechanical reconfiguration in response to external stimuli and offer great potential for various applications including sensors, , wearable devices, artificial muscles, − soft robotics, − biomedicine, and energy harvesting. − Aside from conformability and complicated motion, soft actuators provide significant weight and energy consumption benefits over rigid actuators. As opposed to mechatronic control of traditional actuation systems, soft actuators can be driven by heat, − light, − air pressure, , electricity, − or liquid displacement …”