Multi-scale GO/CNT/AlN nanocomposites for high-performance flexible electrothermal film heaters

Electrothermal materials with low energy consumption and high stability are in high demand for improving our daily life. Here we propose a novel high-performance flexible heater with a high heating rate through screen printing, based on multi-scale nanocomposites comprised of multilayer graphene oxide (ML-GO), carbon nanotubes (CNTs) and aluminum nitride (AlN). The results show that AlN can fill the gaps in the network structure, reducing the surface thermal resistance and film resistivity, which greatly improves the electrical and thermal conductivity of the flexible heater. The maximum temperature of the ML-GO/CNT/AlN heated film reaches 131.2 °C at 4.5 V, and the thin layer exhibits a low sheet resistance down to 10.27 ± 2.5 Ω sq−1. Meanwhile, the steady temperature and corresponding responsivity of the multi-scale flexible heater are 153% and 57.8% higher than those of the ML-GO-based flexible heater, respectively. Inspiringly, the fluctuation in the steady-state temperature curve is less than 0.8% under random mechanical bending and torsion force. During deicing, a high steady-state temperature can also be observed and the ultra-fast response time is far superior to those of most existing heaters. In addition to that, ML-GO/CNT/AlN heaters present a low driving voltage, excellent flexibility and stability, and can be integrated into various deicing conditions and wearable medical systems without being too picky about the used substrates. They also show great potential for application in various intelligent heating films and open up pathways for wearable heating applications.