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

Abstract TiO 2 modified Co 3 O 4 acicular nanotube arrays (ANTAs) have been fabricated in this study, showing a good performance in glucose detection. In the experiment, the precursor Co(CO 3 ) 0.5 (OH)·0.11H 2 O 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(CO 3 ) 0.5 (OH)·0.11H 2 O ANWAs was completely converted to the black Co 3 O 4 ANTAs thin film by alkaline treatment. After the decoration of TiO 2 , the TiO 2 /Co 3 O 4 ANTAs electrode exhibits a much higher current response to glucose compared with the Co 3 O 4 ANTAs. Importantly, this neotype composite structure of Co 3 O 4 enhances the glucose sensing performance by increasing specific surface area, additional reactive sites and synergistic effect, which make the TiO 2 /Co 3 O 4 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 TiO 2 /Co 3 O 4 ANTAs modified electrode exhibits a high selectivity for glucose in human serum, against ascorbic acid and uric acid.