Fabrication of a New Self-assembly Compound of CsTiNbO with Cationic Cobalt Porphyrin Utilized as an Ascorbic Acid Sensor.

A novel sandwich-structured nanocomposite based on TiNbO nanosheets and cobalt porphyrin (CoTMPyP) was fabricated through electrostatic interaction, in which CoTMPyP has been successfully inserted into the lamellar spacing of layered titanoniobate. The resultant TiNbO/CoTMPyP nanocomposite was characterized by XRD, SEM, TEM, EDS, FT-IR, and UV-vis. It is demonstrated that the intercalated CoTMPyP molecules were found to be tilted approximately 63° against TiNbO layers. The glass carbon electrode (GCE) modified by TiNbO/CoTMPyP film showed a fine diffusion-controlled electrochemical redox process. Furthermore, the TiNbO/CoTMPyP-modified electrode exhibited excellent electrocatalytic oxidation activity of ascorbic acid (AA). Differential pulse voltammetric studies demonstrated that the intercalated nanocomposite detects AA linearly over a concentration range of 4.99 × 10 to 9.95 × 10 mol L with a detection limit of 3.1 × 10 mol L at a signal-to-noise ratio of 3.0.