Ti3C2Tx/PANI composites with tunable conductivity towards anticorrosion application

Abstract Introduction of MXene nanoflakes into organic coating is critical for enhancing mechanical properties and corrosion protection, relying on its characteristic structure and nature. But considering the high conductivity of Ti3C2Tx, it may accelerate the corrosion of steel substrate once forming an electrode, so tailoring its conductivity is of great concern. Herein, three-dimensional (3D) Ti3C2Tx/polyaniline composites (TPCs) were synthesized by oxidative polymerization of aniline monomers in Ti3C2Tx dispersion. Of great significance is to achieve the tunable conductivity from 1307 S·cm−1 (Ti3C2Tx MXene) to 0.5 S·cm−1 (TPCs) via controlling polyaniline. The correlation between the anticorrosion ability and own structure/performance of TPCs-containing coatings was assessed by multiple methods. The results demonstrate that 3D TPCs can remarkably enhance the corrosion protection, especially multilayer TPCs12-containing coating (MTPCs12, where TPCs12 denotes that the mass ratio of Ti3C2Tx MXene and aniline was 1:2) with the best anticorrosion performance. The open circuit potential (OCP) and impedance modulus of MTPCs12 can achieve a value of approximately 0.2 V vs. SCE after three hours immersion and 1.05 × 107 Ω·cm2 after 5 weeks immersion, respectively. 3D TPCs with tunable performance characteristic contribute to such an excellent corrosion protection because they can serve as a reservoir and trap caustic ions. Prospectively, TPCs show promising potentials for water splitting, desalination, electronic devices, and other desirable fields. This work not only highlights the application potential of TPCs as an effective anticorrosion material, but also broadens the application of Ti3C2Tx MXene.