Abstract

Hydrogen is considered as one of the best possible energy vector that can effectively store the otherwise intermittent solar energy for proficient renewable energy usage. Conversion of protons to hydrogen is the heart of this scheme and this reaction requires the presence of a catalyst. Currently, the expensive Platinum (Pt)‐ based materials are available as one of the best catalysts but its low abundance is a barrier for its worldwide usage. Naturally occurring [FeFe]‐ and [NiFe]‐hydrogenases can also efficiently perform the H₂ production reaction albeit only in a narrow chemical space (25‐40 °C, pH 4‐8, mostly in absence of O₂). In the past decade, hydrogenase enzyme structures acts as the template for the development of numerous structural and functional model complexes. Macro cyclic cobalt complexes and nickel bis‐ (diphosphine) complexes containing pendant basic groups have emerged as most efficient catalysts, which are active even in heterogeneous conditions (immobilized on electro active surfaces).

Keywords: Bio‐Inspired; Mimics; Catalyst; Hydrogen; Hydrogenase; Amino acid

Abbreviations: Arg: Arginine; Bz: Benzyl; Gly: Glycine; HER: Hydrogen Evolution Reaction; kDa: KiloDalton (mass unit); OCS: Outer Coordination Sphere; P2N2: 1,5‐diaza‐3,7‐diphosphacyclooctane; Phe: Phenyl; PY: Pyridine; SHE: Standard Hydrogen Electrode; TFA: Trifluoro Acetate