Accelerating H Evolution by Anodic Semi-dehydrogenation of Tetrahydroisoquinolines in Water over Co O Nanoribbon Arrays Decorated Nickel Foam.

Coupling the H evolution reaction in water with thermodynamically favorable organic oxidation reactions is highly desirable, because it can enhance the energy conversion efficiency compared with electrocatalytic water splitting, and produce value-added chemicals instead of O in the anodic reaction. Herein, Co O nanoribbon arrays in situ grown on nickel foam (Co O @NF) was employed as an effective electrocatalyst for the selective oxidation of tetrahydroisoquinolines (THIQs). Various value-added semi-dehydrogenation products including dihydroisoquinolines with electro-deficient or -rich groups could be obtained with moderate yields and faradaic efficiencies. Benefitting from the rich surface active sites of Co O @NF, a two-electrode (Co O @NF||Pt) electrolytic system drove a benchmark current density of 10 mA cm at a cell voltage as low as 1.446 V in 1.0 M KOH aqueous solution containing 0.02 M THIQ, which was reduced by 174 mV in comparison with that of overall water splitting.