Morphology control of 3D-networked boron-doped diamond nanowires and its electrochemical properties

3D-networked boron-doped diamond (BDD) nanowire was synthesized using an electrostatic self-assembly technique and a chemical vapor deposition process. This BDD nanowire was a BDD-CNT core-shell hybrid nanostructure and applied as an active electrode material on electrochemical sensor. Because electrochemical sensing performance is generally affected by its surface structure and interface characteristics, the deposition time was controlled to identify the optimal morphology. As the deposition time increased, the BDD-CNT nanostructures became thicker, while their porosity and electron transfer resistance were smaller. The electrochemical properties of the BDD based electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The BDD-CNT electrodes had the significantly higher sensitivity and wider linear range than the BDD electrode due to large surface area and low electron transfer resistance. The BDD-CNT 40 electrode exhibited a highest sensitivity (275.27 μA/mM∙cm2). Therefore, the 3D-networked BDD nanostructures can be applied for electrochemical detection of various analytes as a promising electrode material.