Bioelectrocatalysis: Achievement of Limiting Enzyme Performance Characteristics in Acceleration of Electrode Reactions

摘要

The anticipated crisis in energy production has stimulated a search for alternative energy sources. The only useful alternative to platinum based electrocatalysis for H2 oxidation is bioelectrocatalysis by hydrogenases, first reported by our group 25 years ago [1]. Bioelectrocatalysis is a phenomenon of acceleration of electrode reactions by the enzymes. Direct bioelectrocatalysis presumes the direct electron exchange between the enzyme active site and the electrode without any use of diffusion free mediators. After immersion into H2-saturated solution, the hydrogenase electrode reached the equilibrium hydrogen potential. At positive overvoltages the hydrogenase electrode generated high anodic current, which can be attributed only to hydrogen oxidation. Cathodic current at negative overvoltages has been proven to occur due to H2 evolution.