Catalytic synthesis of the ZnO-carbon nanofilament composite for sensor applications

We have studied to synthesize a ZnO-carbon nanofilament composite (ZnO-CNF) as it is expected to yield an interesting properties for sensor applications. The ZnO-CNF is considered to have a large surface area and a high electrical conductivity. The ZnO-supported Co catalysts were used for the synthesis of the ZnO-CNF. In order to fabricate a pattern of the composite for a biosensor, we have tried to prepare a paste from the composite for a screen-printing. We found that Co loaded catalysts exhibited a high catalytic activity for the carbon yields. SEM observation revealed that fibriform carbon deposits were obtained on the surface of the ZnO powder. In the case of using the Co-loaded ZnO catalyst, we found that the diameter of the fibriform carbon nanomaterial depended on the C₂H₄ concentration in the reaction gas. The reaction conditions are important to control the diameter of the fibriform carbon nanomaterial. The ZnO-CNF paste consisted of the ZnO-CNF, ethyl cellulose, and 2-(2-Butoxyethoxy) ethanol was prepared. The line patterns having 150 mupm were successfully fabricated with using the paste by screen-printing method.