Abstract

Environmental pollution caused by increased emission of CO₂ is one of the biggest global issues in the 21^st century. Among the several other methods to reduce CO₂ in the atmosphere, utilization of CO₂ by electrocatalytic reduction to get chemical species such as oxalic or formic acid has received a considerable attention at present. Related to this issue, our research team mainly focuses on the synthesis of efficient electrocatalysts to bind and reduce CO₂. The work reported herein describes the electrocatalytic reduction of CO₂ by (bis(salicylaldehyde)ethylenediamino)Ni(II)([Ni(Salen)]) complex. Cyclic voltametric studies, carried out in DMF using tetraethylhexaflouro phosphate (TEHFP) as the electrolyte, at a glassy carbon electrode revealed that [(Ni²⁺Salen)/ (Ni+Salen)] reduction takes place at -1.8 V and the reduced form of the [Ni(Salen)] complex is capable of catalyzing CO₂ reduction around -1.8 V. The efficiency of the reduction process in terms of i (CO₂) / i (N₂) ratio is 1.10. The peak-to-peak separation <em>Ep</em> of 200 ± 2 mV is much bigger than the expected value for an electrochemically reversible process (57) mV that involves one electron transfer. The large <em>Ep</em> is an indicative of the involvement of multi-electron reduction process.