Crafting Fast and Efficient H<sub>2</sub>Evolution Electrocatalysts with Tactical Inclusion of Nucleobases
Ab Qayoom Mir, Srewashi Das, Surabhi Rai, Naseer Ahmad Shah, Piyali Majumder, Arnab Dutta
Abstract
In order to achieve a hydrogen-driven energy infrastructure that is carbon-neutral, it is imperative that there be a synthetic catalyst that is developed from a non-noble metal. The unique interplay between the abundant transition metal containing an active site and the surrounding protein-based outer coordination sphere (OCS) is the essence of the remarkable H 2 production displayed by hydrogenase enzymes. Here, we report a series of biomimetic cobalt complexes [Co(dimethylglyoxime) 2 (N nucleobase derivative )Cl] crafted by strategic incorporation of a nucleobase and its derivatives (adenine, adenosine, adenosine monophosphate and hypoxanthine) around a common template. The nucleoside- and nucleotide-appended complexes electrocatalyze H 2 evolution from neutral aqueous solutions at a rapid rate (turnover frequencies of ∼13 000 and ∼12 000 s –1, respectively) while operating at an overpotential of <400 mV. The intricate proton exchange network created between the different fractions of nucleobase derivatives is one of the prime reasons behind such fast and energy-efficient catalysis.