Electrochemical Investigations on the Inactivation of the [FeFe] Hydrogenase from Desulfovibrio desulfuricans Desulfovibrio desulfuricans by O 2 2 or Light under Hydrogen‐Producing Conditions

摘要

Abstract The applicability of the extremely active [FeFe] hydrogenase from Desulfovibrio desulfuricans in H 2 ‐producing devices is studied. Despite being the most active enzyme for H 2 catalysis, its high sensitivity towards O 2 has prevented its use in electrolytic water splitting cells. Using electrochemical methods, the catalytic activity of the enzyme at H 2 ‐producing potentials and its inactivation upon exposure to limited amounts of O 2 or under illumination is analysed. This enzyme is shown to maintain H 2 production activity for extended periods of time at low potentials. At such potentials, the enzyme can deliver the required electrons to fully reduce O 2 to H 2 O, minimising the damage of the enzyme. Additionally, the robustness of this enzyme under illumination at negative applied potentials is demonstrated. These results show that the [FeFe] hydrogenase from D.?desulfuricans is an excellent candidate to be used in devices to store solar energy in hydrogen.