Enhanced electrocatalytic activity and stability of platinum, gold, and nickel oxide nanoparticles-based ternary catalyst for formic acid electro-oxidation

• Published in: International journal of hydrogen energy 2014-08, Vol.39 (23), p.11955-11962
• Main Authors: El-Nagar, Gumaa A., Mohammad, Ahmad M.
• Format: Article
• Language: English
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Catalysts; Direct formic acid fuel cells; Electrocatalysis; Electrodes; Energy; Exact sciences and technology; Formic acid; Fuels; Gold; Gold nanoparticles; Hydrogen; Nanoparticles; Nanostructure; Nickel oxide nanoparticles; Platinum; Platinum nanoparticles; Surface chemistry; Third body
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2014.06.028

The global interest to realize and commercialize the direct formic acid fuel cells has motivated the development of efficient and stable anodes for the formic acid (FA) electro-oxidation (FAO). In this investigation, a ternary catalyst composed of Pt nanoparticles (PtNPs), Au nanoparticles (AuNPs) and nickel oxide nanoparticles (nano-NiOx), all were sequentially electrodeposited onto the surface of a glassy carbon (GC) electrode, was recommended for this reaction. The surface morphology investigation revealed the deposition of grain-shaped PtNPs (25 nm average particle size), and flower-shaped nanospheres (less than 60 nm average particle size) of AuNPs and nano-NiOx. Interestingly, the ternary modified NiOx-Au-Pt/GC electrode has shown an outstanding electrocatalytic activity towards the direct FAO, concurrently with a complete suppression for the indirect route. It further exhibited excellent stability that extended for 7 h of continuous electrolysis. While PtNPs furnished a suitable base for FA adsorption, AuNPs played a significant role to interrupt the contiguity of the Pt surface sites, which is necessary for CO poisoning. On the other hand, nano-NiOx acted as a catalytic mediator facilitating the charge transfer of FAO and the oxidative removal of CO at a lower potential. •A ternary modified GC catalyst was developed for the formic acid electro-oxidation (FAO).•The catalyst’ preparation involved a sequential deposition of Pt, Au, and NiOx nanoparticles onto GC substrate.•A superb enhancement in the catalytic activity of the direct FAO was achieved.•The catalyst exhibited excellent stability extended for 7 h of continuous electrolysis.•The β-NiOOH is believed to mediate the oxidation facilitating the electron transfer.