Facile and fast fabrication of polyaniline nanorods on acidized titanium foils with a synergistic effect for electrochemical sensing

Abstract

A facile method to quickly construct polyaniline nanorods (PANI-NR) on acidized titanium (Ti) foils was reported. In this strategy, the acidized Ti foils (Ti-ac) can act as nucleation sites for controllable growth of PANI-NR. Attributed to the synergistic effect of the PANI-NR, doped CNTs and Ti-ac, the PANI-NR/CNT/Ti-ac composite exhibited decreased redox potential and improved electron transport capability. PANI-NR/CNT/Ti-ac was used as an excellent platform for electrochemically sensing ascorbic acid (AA). At a low AA concentration range from 0.4 μM to 125 μM (R² = 0.998), a high sensitivity of 281 μA mM⁻¹ cm⁻² was obtained. The detection limit of AA was 80 nM at a signal-to-noise ratio of 3, which was better than that of reported PANI microtubes (280 nM), PANI nanoparticles (8.3 μM) and PANI film/PAA/MWCNTs (250 nM). A strategy for fabricating the PANI-NR/CNT composite on Ti-ac was provided and the improved electrochemical performance suggests promising application of PANI-NR/CNT/Ti-ac as a sensing platform.