Electrochemical formation of multilayered NiO film/Ni foam as a high-efficient anode for methanol electrolysis

Abstract

A multilayered NiO film is fabricated on 3D Ni foam (NF) substrate via electrochemical cyclic voltammetry (CV) as a high-efficient methanol oxidation catalyst. We carefully studied the formation mechanism of an as-fabricated electrode and found that lower cathode potential in CV plays a key role in constructing the microstructure of this material. The as-synthesized electrode shows remarkable electrocatalytic methanol oxidation activity (161.5 mA cm−2 in 1 M KOH with 0.3 M methanol) and good stability (current retention >92% after 500 cycles) in three-electrode measurement. Moreover, the NiO film/Ni foam is further used as anode catalyst in two-electrode configured methanol-water solution electrolysis. A sharp decline of cell voltage is observed (∼170 mV) when 0.1 M methanol was added in alkaline solution. In addition, the methanol-water solution electrolysis also exhibits lower electric energy consumption (∼41.87 KWh kg−1 Hydrogen@200 mA cm−2) for hydrogen production.