Onsite Deposition of Self-Repairing Biomimetic Nanostructured Ni Catalysts with Improved Electrocatalysis toward Glycerol Oxidation for H2 Production

In this study, a technology was developed for producing hydrogen via glycerol electrolysis. A homogeneous stock solution of a Ni catalyst was prepared, conserved and used for an alkali electrolyte with no precipitation due to the coordinative and protective effects of sodium tartrate and polyvinyl pyrrolidone (PVP). The deposition of the Ni(OH)(2) catalyst and its electrocatalysis toward glycerol occurred nearly simultaneously. Tedious and laborious procedures for preparing common catalysts and immobilizing them on an electrode surface were not required. The Ni(OH)(2) catalyst film self-repaired due to the presence of Ni in the alkali electrolyte. This technique also exhibited satisfactory electrocatalytic performance for hydrogen production via glycerol electrolysis with a high transformation efficiency and good stability. The Ni(OH)(2) electrocatalyst electrolyzed glycerol at the glassy carbon anode to produce H2O and CO2, and this H2O was electrochemically reduced at the Pt cathodic electrode to release H-2. The formation of bubbles and the presence of PVP provided the anodic electrode surface a brilliant iridescence similar to that of butterfly wings due to the distributed Ni(OH)(2) nanostructures with large circular spaces and small nanoholes. Such systems using an abundance of the non-noble metal Ni have potential applications for solar energy and fuel cell development. (C) 2015 Elsevier Ltd. All rights reserved.