TY - GEN
T1 - PT and PTCO electrocatalysts prepared by mechanical alloying and metal organic chemical vapour deposition for the oxygen reduction reaction in alkaline media
AU - García-Contreras, M. A.
AU - Fernández-Valverde, S. M.
AU - Vargas-García, J. R.
PY - 2008
Y1 - 2008
N2 - Pt and Pt-Co (70-30) Electrocatalysts were obtained by Mechanical alloying (MA) of Pt and cobalt powders. They also were prepared as thin films on glassy carbon by chemical vapour deposition CVD of metal organic precursors of Pt and Co. The MA electrocatalysts consisted of agglomerated particles constituted of 20-25 nm crystallites. The CVD films had about 250 nm of thickness and the particles size was about 30 nm for Pt particles and 19 nm for Pt-Co particles. Some iron was determined by EDX 0.9% in Pt and 3.1% in Pt-Co for the samples prepared by MA. Tafel plots were performed for the elecrocatalysts obtained by both techniques, and the kinetic parameters for the ORR were determined. The results showed that PtCo alloys obtained by both techniques have higher exchange current densities than Pt prepared in the same conditions. The difference is higher for the materials prepared by MA. The Koutecky-Levich plots were compared with 2 and 4 electron pathways for the ORR: The MA and CVD obtained electrocatalysts showed a 4 electron transfer for the ORR.
AB - Pt and Pt-Co (70-30) Electrocatalysts were obtained by Mechanical alloying (MA) of Pt and cobalt powders. They also were prepared as thin films on glassy carbon by chemical vapour deposition CVD of metal organic precursors of Pt and Co. The MA electrocatalysts consisted of agglomerated particles constituted of 20-25 nm crystallites. The CVD films had about 250 nm of thickness and the particles size was about 30 nm for Pt particles and 19 nm for Pt-Co particles. Some iron was determined by EDX 0.9% in Pt and 3.1% in Pt-Co for the samples prepared by MA. Tafel plots were performed for the elecrocatalysts obtained by both techniques, and the kinetic parameters for the ORR were determined. The results showed that PtCo alloys obtained by both techniques have higher exchange current densities than Pt prepared in the same conditions. The difference is higher for the materials prepared by MA. The Koutecky-Levich plots were compared with 2 and 4 electron pathways for the ORR: The MA and CVD obtained electrocatalysts showed a 4 electron transfer for the ORR.
KW - Chemical vapour deposition
KW - Electrocatalysts
KW - Mechanical alloying
KW - Oxygen reduction reaction
UR - http://www.scopus.com/inward/record.url?scp=84866322985&partnerID=8YFLogxK
M3 - Contribución a la conferencia
AN - SCOPUS:84866322985
SN - 9781615674541
T3 - 17th World Hydrogen Energy Conference 2008, WHEC 2008
SP - 874
EP - 878
BT - 17th World Hydrogen Energy Conference 2008, WHEC 2008
T2 - 17th World Hydrogen Energy Conference 2008, WHEC 2008
Y2 - 15 June 2008 through 19 June 2008
ER -