Microstructures and electrothermal characterization of aromatic poly(azomethine ether)‐derived carbon films

We report the microstructural evolution and electrothermal properties of aromatic poly(azomethine ether) (PAME)‐derived carbon films, which were fabricated by a facile spin‐coating and following carbonization at different temperatures of 300–1,000°C. For the purpose, poly[3‐(4‐nitrilophenoxy)phenylenenitrilomethine‐1,3‐phenylenemethine] (mPAME) with a high residue of ~56.4 wt% after carbonization at 1,000°C was synthesized for a polymeric precursor for carbon films. The X‐ray photoelectron spectroscopy, Raman spectroscopy, and X‐ray diffraction analyses revealed that the molecular structures of mPAME films changed into an intrinsically nitrogen‐doped graphitic structure, dominantly at the carbonization temperatures of 800–100°C. The electrical conductivity increased considerably from ~10−7 S/cm for mPAME‐derived films fabricated at 300–700°C to ~100 S/cm for the film carbonized at 800°C to ~101 S/cm for the films carbonized at 900–1,000°C. Accordingly, mPAME‐derived carbon films, which were carbonized at 900–1,000°C, exhibited excellent electrothermal performance, such as rapid temperature responsiveness, high maximum temperatures, and high electric power efficiency to relatively low applied voltages of 5–13 V.