Facile method to synthesize a carbon layer embedded into titanium dioxide nanotubes with metal oxide decoration for electrochemical applications

Abstract

We report a facile and economical method to form a carbon layer embedded into self-organized titanium dioxide nanotubes (C/TiO₂ NTs) with a double-walled morphology using a one-step pyrolysis method. The carbon precursors are the organic electrolyte remaining in the nanotube channels during the anodic growth of the TiO₂ nanotubes (TiO₂ NTs). By combining a layer-by-layer (LBL) technique with a galvanic displacement reaction, noble oxide nanomaterials can be anchored onto the nanotubes. Using RuO₂ as a model, the formed TiO₂/C–RuO₂ NT ternary composite exhibits significantly enhanced pseudocapacitive properties with a capacitance value up to 14 times higher than bare TiO₂ NTs and a high utilization efficiency of RuO₂ (1089 F g⁻¹). Additionally, the composite shows a satisfactory long-term cycling stability with only a 7% decrease after 500 cycles. This strategy opens up a platform to enhanced functionality of TiO₂ NTs for novel electrochemical applications.