Flexible and conductive titanium carbide-carbon nanofibers for the simultaneous determination of ascorbic acid, dopamine and uric acid.

The development of novel materials for facile, cost-effective and quick practical application is a demanding research interest in electroanalytical chemistry. Titanium carbide (TiC), as one of the most important transition metal carbides, exhibits good chemical stability and electrical conductivity, and its electrocatalytic activity resembles that of metals, but is much cheaper. In this work, TiC nanoparticle (NP) loaded carbon nanofiber (CNF) films (TCNFs) are synthesized using an electrospinning and carbothermal technique, which facilely maintains their structural integrity with robust adhesion. Uniform TiC NPs are firmly embedded in the surface of CNFs, which integrates the large surface area and unique 3D, porous network structure of CNFs with the good conductivity and excellent electrocatalytic activity of TiC NPs. Simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA) and uric acid (UA) at TCNFs displays excellent peak current signals with well-defined peak potentials. The linear ranges are 0.001-1.5 mM, 0.05-160 μM and 0.001-0.875 mM for AA, DA and UA, and the corresponding detection limits are 0.3 μM, 20 nM and 0.3 μM, respectively. In addition, TCNFs show long-term sensing stability and potential applications in real samples, and behave as good anti-interference agents towards KNO, ZnSO, glucose, etc. Most importantly, unlike some common carbon-based electrochemical sensor systems, an adsorption-less response is observed for the test analytes at the TCNF electrode. TCNFs show interesting potential as candidates for the construction of electrochemical sensors.