Development of Bismuth‐Modified PtPd Nanocatalysts for the Electrochemical Reforming of Polyols into Hydrogen and Value‐Added Chemicals. Issue 10 (2nd August 2016)

• Record Type: Journal Article
• Authors: González‐Cobos, Jésus; Baranton, Stève; Coutanceau, Christophe
• Is Part Of: ChemElectroChem. Volume 3:Issue 10(2016)
• Page Start: 1694
• Page End: 1704
• Publication Date: 2016-08-02
• Subjects: electrochemistry -- glycerol -- hydrogen -- IR spectroscopy -- oxidation; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201600147
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: Different PtPd nanostructured catalysts modified with bismuth have been synthesized on a carbon support. Their activity towards the glycerol electrooxidation reaction has been compared in alkaline medium, and modification with about 10 at % bismuth led to an increase in activity compared with pure metals. Pt9 Bi1 /C is the most active catalyst for this reaction, with an oxidation onset potential as low as 0.3 V versus RHE. The hydrogen production in a direct electrolysis cell was evaluated. The Pt9 Bi1 /C anode gave a hydrogen production rate of approximately 0.11 and 0.23 Nm H 2 3 h −1 m −2 with an electrical energy consumption of 1.3 or 1.65 kWh (Nm H 2 3 ) −1 at 0.55 or 0.7 V, respectively. Compared with traditional water electrolysis, this is an energy saving of between 66 and 57 %. It was also shown by using in situ FTIR spectroscopy that the modification of platinum with bismuth avoids (or at least drastically reduces) C−C bond breakage, which thus increases selectivity towards value‐added C3 compounds. At low potentials, glyceraldehyde is the main reaction product and at higher potentials, glyceraldehyde and dihydroxyacetone act as reaction intermediates to the formation of carboxylates. Abstract : Bi adding value ! Bismuth‐modified PtPd anodes allow the production of hydrogen in an alkaline electrolysis cell at potentials as low as 0.3 V. Product identification by using FTIR spectroscopy indicates that glyceraldehyde and dihydroxyacetone are selectively formed at anode potentials lower than 0.55 V, whereas value‐added C3 carboxylates are produced at anode potentials higher than 0.6 V. In addition, modification with bismuth avoids C−C bond breakage.