Niobium Enhances Electrocatalytic Pd Activity in Alkaline Direct Glycerol Fuel Cells. Issue 21 (18th September 2019)

• Record Type: Journal Article
• Authors: Souza, Felipe M.; Böhnstedt, Paula; Pinheiro, Victor S.; Paz, Edson C.; Parreira, Luanna S.; Batista, Bruno L.; Santos, Mauro C.
• Is Part Of: ChemElectroChem. Volume 6:Issue 21(2019)
• Page Start: 5396
• Page End: 5406
• Publication Date: 2019-09-18
• Subjects: alkaline direct glycerol fuel cells -- electrocatalysis -- glycerol oxidation reaction -- palladium -- niobium; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201901254
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: Pd x Nb y /C binary electrocatalysts supported on Printex 6 L carbon black were prepared by using an adapted chemical reduction method with sodium borohydride. The electrocatalysts were characterized by using SEM, TEM, XRD, EDS, ICP‐MS, water contact angle and Raman spectroscopy. The best performance for the alkaline direct glycerol fuel cell (ADGFC) was obtained by using Pd1 Nb1 /C, which yielded a maximum power density of 27 mW cm −2 at 70 °C. Residues of products formed from the glycerol oxidation were analyzed by using FT‐Raman and high‐performance liquid chromatography (HPLC). The Pd1 Nb1 /C electrocatalyst exhibited a more negative onset potential for the CO oxidation reaction and a higher conversion rate of glycerol to carbonate. We suggest that the higher hydrophilicity, higher degree of disorder, and bifunctional effects enhanced the electrocatalytic activity of Pd, as Nb facilitated the oxidation of adsorbed CO in Pd and increased the transfer rate of electron from Pd to carbon black support Therefore, Nb is a promising co‐catalyst for Pd‐based electrocatalysts for ADGFCs. Abstract : Feeling GORgeous : Niobium is investigated as both the auxiliary to Pd metal in the glycerol oxidation reaction (GOR) and as a carbon surface modifier to obtain the aforementioned effects. Pd x Nb y binary electrocatalysts supported on Printex 6 L carbon black are investigated and extensively characterized. This comparative study will contribute to the understanding of the role of Nb in improving the electrocatalytic Pd activity in the GOR.