Electrochemical Activation of Silicon: Enhancing Hydrogen Production from FeNi Electrocatalysts

A two-sided electrode composed of Fe_xNi_100-xO_yand Si was implemented to produce hydrogen. The hydrogen evolution reaction is facilitated by the Fe_xNi_100-xO_yelectrocatalyst. The high pH of the alkaline electrolyte and the reducing potential of the electrode result in the activation of the Si side, allowing spontaneous production of H₂. Results demonstrate that the Fe_xNi_100-xO_ycomposition and the electrolyte composition influence the performance of the Fe_xNi_100-xO_y/Si system. The activation and subsequent production of H₂by the Si was demonstrated to be favored in 0.1 M KOH and NaOH electrolytes over LiOH, and this result was consistent when the electrochemical cell was operated under applied voltage and at open circuit voltage. At the same time, results showed that the Fe₈₀Ni₂₀/Si composition maintained a current of -10 mA at a lower potential (∼50 mV) compared to the Fe₂₀Ni₈₀/Si composition. Overall, the results of this study demonstrate that the two-sided Fe_xNi_100-xO_y/Si electrode can be used to boost the production of hydrogen, leading to a maximum of 140% H₂efficiency, which includes both Faradaic H₂production and non-Faradaic H₂evolution through Si corrosion.