From Hydrogenases to Noble Metal–Free Catalytic Nanomaterials for H 2 Production and Uptake

Abstract
Electrolysis at Nickel: One drawback of solar and wind power is the need for an efficient storage system to release accumulated energy when neither source is readily available (during still nights, for example). Hydrogen derived from electrolysis of water is potentially a useful medium for this purpose, but catalyzing the interconversion efficiently at large scale would currently require a substantial amount of the scarce precious metal platinum. An alternative approach would be to mimic natural enzymatic reactions, which accomplish the interconversion using hydrogenases that incorporate the more abundant metals iron and nickel. In this vein, Le Goff et al. (p. 1384 ; see the Perspective by Hambourger and Moore ) have lightly modified a hydrogenase-inspired nickel complex in order to append it to a conductive carbon nanotube support. The resulting hybrid material shows promising catalytic efficiency for reversible aqueous electrolysis in a standard apparatus.