Enhancement of charge transfer rate at mixed morphology TiO2/graphene interface by Al3+

Applying conductive coatings on the surface of non-conductive materials can effectively reduce the hazards caused by static electricity during the production process. However, commercially available TiO2 conductive powder relies on rare minerals and produces waste acids and bases. Therefore, we prepared Al-doped TiO2/graphene composites, which combine the advantages of TiO2 homojunction, ion doping, heterojunction, and rod morphology with excellent electrical conductivity (0.161 Ω·cm). In particular, the doping of Al3+ doubles its conductivity. This is due to the introduction of Al3+, which generates oxygen vacancies and so increases the carrier concentration. Furthermore, the introduction of Al3+ generates new conductive pathways (Al–O–C) and increases the content of highly electrochemically active oxygen-containing functional groups, leading to a significant enhancement of carrier transfer efficiency. Accordingly, the enhanced carrier concentration and transfer efficiency enhance the conductive properties of T-G-Al and provide new ideas for the preparation of conductive coatings.