Development of a Simple and Cheap Conductive Graphite Ink
Ana Elisa Ferreira Oliveira, Arnaldo César Pereira
Abstract
Several efforts were made to fabricate a graphite ink easy to prepare, cheap, and with good conductivity. The proposed ink composition was graphite and nail polish (50:50%), using acetone as an organic solvent. The materials were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, electrochemidal impedance spectroscopy, and electrochemical measurements. The results confirmed the conductive nature of graphite and the insulator nature of nail polish. Although nail polish is an insulator, it acts as a binder, improving the ink adhesion and does not harm the ink conductivity. The result was a well-dispersed ink that cost $0.034 ml−1 with an average ohmic resistance of 2.17 kΩ. The electrochemical behavior was also investigated, showing a low background current and a well-defined peak corresponding to the redox probe. This indicates that the graphite ink can be used in the fabrication of electrochemical sensors.