TiO2 decorated Co3O4 acicular nanotube arrays and its application as a non-enzymatic glucose sensor

TiO2 modified Co3O4 acicular nanotube arrays (ANTAs) have been fabricated in this study, showing a good performance in glucose detection. In the experiment, the precursor Co(CO3)0.5(OH)·0.11H2O acicular nanowire arrays (ANWAs) was first grown on the fluorine doped tin oxide (FTO) substrate by a hydrothermal method. Thereafter, the uniform pink precursor Co(CO3)0.5(OH)·0.11H2O ANWAs was completely converted to the black Co3O4 ANTAs thin film by alkaline treatment. After the decoration of TiO2, the TiO2/Co3O4 ANTAs electrode exhibits a much higher current response to glucose compared with the Co3O4 ANTAs. Importantly, this neotype composite structure of Co3O4 enhances the glucose sensing performance by increasing specific surface area, additional reactive sites and synergistic effect, which make the TiO2/Co3O4 glucose sensor show a high sensitivity of 2008.82 μA mM−1 cm−2, a fast response time (less than 5 s) and a detection limit as low as 0.3396 μM (S/N=3). The TiO2/Co3O4 ANTAs modified electrode exhibits a high selectivity for glucose in human serum, against ascorbic acid and uric acid.