Bismuth-modified carbon supported Pt nanoparticles as electrocatalysts for direct formic acid fuel cells

• Published in: Electrochimica acta 2012-02, Vol.63, p.105-111
• Main Authors: Sáez, A., Expósito, E., Solla-Gullón, J., Montiel, V., Aldaz, A.
• Format: Article
• Language: English
• Subjects: Adatom adsorption; Applied sciences; Bi-modified Pt nanoparticles; Carbon; Catalysts; Deposition; DFAFC; Electrodes; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Formic acid; Formic acid electrooxidation; Fuel cells; Nanoparticles; Platinum
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2011.12.076

► Bi-modified Pt nanoparticles supported on carbon have been employed as anode electrocatalyst for a direct formic acid fuel cell (DFAFC). ► Bi-modified Pt nanoparticles have been proved to be good catalysts for formic acid oxidation. ► Bi-modified coated catalyst membranes have been used in a breathing direct formic acid fuel cell. ► Polarization curves have been obtained and a clear activity enhancement in comparison with the unmodified Pt nanoparticles has been observed. Bismuth-modified Pt nanoparticles supported on carbon have been employed as anode electrocatalyst for a direct formic acid fuel cell (DFAFC). Two different types of electrodes were used: a thin layer Pt/C working electrode deposited on a gold substrate and a coated catalyst (Pt/C) membrane. Bismuth was deposited on the Pt nanoparticles by irreversible adatom adsorption from a Bi3+ solution. Bi-modified thin-film working electrodes with different catalyst loadings (0.1, 0.5 and 1.0mgPtcm−2) were tested for the electrooxidation of formic acid (2, 4.75 and 9M formic acid solutions). Likewise, a Bi-modified coated catalyst membrane was used as anode in an air-breathing direct formic acid fuel cell. For this cell, polarization curves were obtained for different formic acid solutions. Independently of the type of electrodes, the presence of Bi caused a four/six fold increase of the electrooxidation currents as compared to unmodified Pt electrodes. Thus, the use of bismuth-modified carbon supported Pt nanoparticles is presented as an easy, feasible and versatile alternative for improving the efficiency of DFAFCs.