Cathodic Using of ZrB₂-<i>α</i>SiC and TiB₂-<i>α</i>SiC for PEM Electrolysis and Water Electrolysis at Low Temperature

Abstract

39 mol% SiC of ceramic pellets ZrB 2 - α SiC and TiB 2 - α SiC were synthesized by the reactive hot pressure RHP process at 1850&deg;C under 40 Mpa in vacuum. The XR diffraction displays the absence of other reagents apart from ZrB 2 , SiC and TiB 2 confirming the purity of the pellets. The cathodic exploitation of both of them through electrochemical study shows that TiB 2 - α SiC is the most active for Hydrogen Evolution Reaction (HER) and Hydrogen Oxidation Reaction (HOR) in 0.5 M of H 2 SO 4 solution at room temperature. Moreover, the kinetic exploitation shows that for both pellets the system is controlled by mass transport when they are used as HER. However, in the case of HOR, the system is controlled by the electron transfer.