TY - JOUR
T1 - Activity and stability of carbon supported PtxY alloys for the ORR determined by RDE and single-cell PEMFC measurements
AU - Schwämmlein, Jan N.
AU - Harzer, Gregor S.
AU - Pfändner, Philipp
AU - Blankenship, Andrea
AU - El-Sayed, Hany A.
AU - Gasteiger, Hubert A.
N1 - Publisher Copyright:
© The Author(s) 2018. Published by ECS.
PY - 2018
Y1 - 2018
N2 - Bimetallic alloys based on Pt and Y are potential cathode catalysts for proton exchange membrane fuel cells (PEMFCs) due to their high oxygen reduction reaction (ORR) activity. Nevertheless, the synthesis of carbon supported PtxY catalysts is challenging due to the low standard reduction potential of yttrium compared to platinum. Hence, extended electrochemical testing in actual PEMFCs remains elusive, especially with respect to catalyst degradation upon voltage-cycling. In this publication, we present the synthesis of a bimetallic PtxY/C catalyst via impregnation of commercial Pt/C with an yttrium halide precursor and subsequent heat-treatment in H2 at 1200°C. This catalyst showed a high specific ORR activity, at a mass activity similar to Pt/C due to its comparably low electrochemical surface area (ECSA). On the other hand, the large particle size of the here synthesized PtxY/C catalyst (≈10 nm) resulted in a significantly enhanced stability versus degradation in an accelerated stress test (AST) based on voltage-cycling between 0.6 and 1.0 VRHE at 50 mV s−1, showing a superior ECSA, ORR activity and H2/air performance after 30000 cycles compared to a standard Pt/C catalyst.
AB - Bimetallic alloys based on Pt and Y are potential cathode catalysts for proton exchange membrane fuel cells (PEMFCs) due to their high oxygen reduction reaction (ORR) activity. Nevertheless, the synthesis of carbon supported PtxY catalysts is challenging due to the low standard reduction potential of yttrium compared to platinum. Hence, extended electrochemical testing in actual PEMFCs remains elusive, especially with respect to catalyst degradation upon voltage-cycling. In this publication, we present the synthesis of a bimetallic PtxY/C catalyst via impregnation of commercial Pt/C with an yttrium halide precursor and subsequent heat-treatment in H2 at 1200°C. This catalyst showed a high specific ORR activity, at a mass activity similar to Pt/C due to its comparably low electrochemical surface area (ECSA). On the other hand, the large particle size of the here synthesized PtxY/C catalyst (≈10 nm) resulted in a significantly enhanced stability versus degradation in an accelerated stress test (AST) based on voltage-cycling between 0.6 and 1.0 VRHE at 50 mV s−1, showing a superior ECSA, ORR activity and H2/air performance after 30000 cycles compared to a standard Pt/C catalyst.
UR - http://www.scopus.com/inward/record.url?scp=85067602865&partnerID=8YFLogxK
U2 - 10.1149/2.0221815jes
DO - 10.1149/2.0221815jes
M3 - Article
AN - SCOPUS:85067602865
SN - 0013-4651
VL - 165
SP - J3173-J3185
JO - Journal of the Electrochemical Society
JF - Journal of the Electrochemical Society
IS - 15
ER -