Fabrication of vertically-aligned carbon nanotube electrodes using grid-inserted I plasma-enhanced chemical vapor deposition for chemical sensors

Abstract

Vertically-aligned carbon nanotube (CNT) electrodes for chemical sensors were fabricated by using grid-inserted plasma-enhanced chemical vapor deposition (PECVD). A larger detection current was obtained in the CNT electrode than in the Pt electrode on the cyclic voltammetry. It has been demonstrated that each CNT does not work as an independent electrode because of the diffusion layer formed on the CNT electrode surface. The thickness of the diffusion layer was estimated to be about 10 μm by voltammetry using a CNT electrode array with various unit electrode spacings. © 2008 The Japan Society of Applied Physics.