Fiber-shaped dynamic thermal radiation-regulated device based on carbon fiber and polyaniline

Abstract

Electrochromic devices for effective infrared (IR) modulation are receiving increasing attention in engineering. However, the majority of the devices for IR modulations possess planar sandwich structures, restricting their implantation into fabrics and limiting their comfortable wearability due to the bad air permeability. Herein, a fiber-shaped dynamic thermal radiation-regulated device with a novel integrative core-shell structure, based on carbon fiber and polyaniline has been developed. The device with high performance can realize dynamic thermal radiation regulation with the IR emissivity (△ε) as high as 0.4 at 7.5–14 μm. Furthermore, the device can reversibly change color between dark green (in the oxidized state) and golden yellow (in the reduced state) as a response to low applied potentials (−0.5 V and 0.6 V) with fast response time (1.7 s). In addition, the device demonstrates high cycling stability as evident from the current-time (i-t) curve of the reduced and oxidized states as well as stable Δε after 500 cycles. The performances, including △ε and cyclic voltammetry curve (CV) of the device demonstrate no apparent degradation after 500 bending cycles, indicating high durability. This study provides new insights into fiber-shaped dynamic thermal radiation-regulated devices and highlights their applications in personal thermal management, adaptive thermal camouflage, and intelligent wearable devices. • The fiber-shaped dynamic thermal radiation-regulated device based on carbon fiber (core) and polyaniline (electrochromic functional layer) was fabricated. • The device demonstrates an integration of the structure and function design to make the carbon fiber as the substrate and electrode simultaneously, which contributes to an uncomplicated structure. • Under low external voltages, the device can be reversibly transformed from the reduced state with low emittance to the oxidized state with high emittance in fast response time (1.7 s). • The device displays outstanding dynamic thermal radiation regulation (Δε = 0.4 at 7.5–14 μm) and can realize the color transformation between dark green and golden yellow to integrate with the environment. • The device possesses excellent structural stability, mechanical flexibility, cycling stability and durability.