TY - JOUR
T1 - Tuning the Activity of Pt(111) for Oxygen Electroreduction by Subsurface Alloying
AU - Stephens, Ifan
AU - Bondarenko, A.S.
AU - Perez-Alonso, F.J.
AU - Vallejo, Federico Calle
AU - Bech, Lone
AU - Johansson, Tobias Peter
AU - Jepsen, A.K.
AU - Frydendal, R.
AU - Knudsen, Brian Peter
AU - Rossmeisl, Jan
AU - Chorkendorff, Ib
PY - 2011
Y1 - 2011
N2 - To enable the development of low temperature fuel cells, significant improvements are required to the efficiency of the Pt electrocatalysts at the cathode, where oxygen reduction takes place. Herein, we study the effect of subsurface solute metals on the reactivity of Pt, using a Cu/Pt(111) near-surface alloy. Our investigations incorporate electrochemical measurements, ultrahigh vacuum experiments, and density functional theory. Changes to the OH binding energy, ΔEOH, were monitored in situ and adjusted continuously through the subsurface Cu coverage. The incorporation of submonolayer quantities of Cu into Pt(111) resulted in an 8-fold improvement in oxygen reduction activity. The most optimal catalyst for oxygen reduction has an ΔEOH ≈ 0.1 eV weaker than that of pure Pt, validating earlier theoretical predictions.
AB - To enable the development of low temperature fuel cells, significant improvements are required to the efficiency of the Pt electrocatalysts at the cathode, where oxygen reduction takes place. Herein, we study the effect of subsurface solute metals on the reactivity of Pt, using a Cu/Pt(111) near-surface alloy. Our investigations incorporate electrochemical measurements, ultrahigh vacuum experiments, and density functional theory. Changes to the OH binding energy, ΔEOH, were monitored in situ and adjusted continuously through the subsurface Cu coverage. The incorporation of submonolayer quantities of Cu into Pt(111) resulted in an 8-fold improvement in oxygen reduction activity. The most optimal catalyst for oxygen reduction has an ΔEOH ≈ 0.1 eV weaker than that of pure Pt, validating earlier theoretical predictions.
U2 - 10.1021/ja111690g
DO - 10.1021/ja111690g
M3 - Journal article
SN - 0002-7863
VL - 133
SP - 5485
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 14
ER -