This paper presents a novel approach to maximize the current density of electrodes modified by carbon nanotubes for high efficiency hydrogen production. Multi-walled carbon nanotubes (MWNTs), due to their unique electrical conductivity and mechanical properties, have led to our interest in their application of MWNTs for water splitting purposes. This carbon nanotube based electrode, synthesized directly by PECVD, provides a ~6 times enhancement of the water splitting current density compared to a graphite electrode in acidic electrolyte. In addition, our PECVD grown vertically aligned carbon nanotubes shows good adhesion to the graphite substrate and long term sustainability in a strong acid solution without the need for any complicated and expensive pre-treatment. Furthermore, the neutral potassium phosphate solution electrolyte (KPi electrolyte) using cobalt salt as the catalyst, as was proposed recently, has been employed to demonstrate the long term compatibility of this electrode to various environments. The proposed graphite-MWNTs electrodes have been fabricated and tested in various conditions. Finally, performance and sustainability have been demonstrated.
Wang, X., Zhou, H., Li, P., & Shu, W. (2013). Vertically aligned carbon nanotube based electrodes for hydrogen production by water electrolysis. Journal of Materials Research, 28(7), 927-932. https://doi.org/10.1557/jmr.2012.402