Nickel carbonate (Ni(CO)) as an electrocatalyst and photo-electrocatalyst for methanol electro-oxidation

Nickel carbonate was deposited electrochemically on Pt and Pd electrode surfaces by chronoamperometry. The electrodeposited Ni 2 (CO 3 ) 3 /Pt was characterized by a variety of techniques. The electrodeposited Ni 2 (CO 3 ) 3 /Pt and Ni 2 (CO 3 ) 3 /Pd were subsequently used for electrochemical and photoelectrochemical methanol oxidation reactions. The methanol oxidation reaction was studied using cyclic voltammetry and chronoamperometry techniques in the presence of KOH and Na 2 CO 3 media. The electrochemically deposited Ni 2 (CO 3 ) 3 on Pt and Pd electrodes showed enhanced activity towards methanol oxidation in KOH and Na 2 CO 3 electrolytes. Ni 2 (CO 3 ) 3 /Pt displayed the highest forward scan peak current density of 19.8 mA cm −2 at an anodic potential of 0.08 V vs. NHE, whereas Ni 2 (CO 3 ) 3 /Pd displayed the forward scan peak current density of 5.2 mA cm −2 at an anodic potential of 0.2 V vs. NHE in KOH medium. Additionally, Ni 2 (CO 3 ) 3 /Pt and Ni 2 (CO 3 ) 3 /Pd demonstrated good photoelectrochemical activity under UV-light irradiation in KOH and Na 2 CO 3 media. An anodic peak current density of 24.1 mA cm −2 was observed for Ni 2 (CO 3 ) 3 /Pt and 7.4 mA cm −2 for the Ni 2 (CO 3 ) 3 /Pd electrode. The comparison in activity of the Pt and Pd electrodes and the first-row transition metal carbonates namely cobalt and nickel carbonates was suggestive of the superior activity of Ni 2 (CO 3 ) 3 /Pt and Ni 2 (CO 3 ) 3 /Pd catalysts for the electrochemical methanol oxidation reaction. Electrochemical deposition of Ni 2 (CO 3 ) 3 on Pt and Pd electrodes for the methanol oxidation reaction has been reported. The Ni 2 (CO 3 ) 3 /Pt and Ni 2 (CO 3 ) 3 /Pd electrodes show efficient activity for MOR electrochemically as well as photoelectrochemically.