Oxygen Reduction Activity of PtxNi1-x Alloy Nanoparticles on Multiwall Carbon Nanotubes

• Main Authors: Kim, Junhyung (Contributor), Lee, Seung Woo (Contributor), Carlton, Christopher (Contributor), Shao-Horn, Yang (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor), Massachusetts Institute of Technology. Electrochemical Energy Laboratory (Contributor)
• Format: Article
• Language: English
• Published: Electrochemical Society, 2013-10-03T20:16:17Z.
• Subjects: Article
• Online Access: Get fulltext

PtxNi1 - x nanoparticles (Pt:Ni; 1:0, 4:1, 3:1 and 0.7:1) of ~5 nm, were synthesized on carboxylic acid-functionalized multiwall carbon nanotubes (PtxNi1 - x NPs/MWNT). The oxygen reduction reaction (ORR) activity measurements in 0.1 M HClO4 showed an activity order of Pt NPs/MWNTs < Pt4Ni NPs/MWNTs ≈ Pt0.7Ni NPs/MWNTs < Pt3Ni NPs/MWNTs, where Pt3Ni NPs/MWNTs had mass activity 2.5 times higher than a commercial 46 wt % Pt/C catalyst. The enhanced ORR activity of Pt3Ni NPs relative to Pt NPs could be attributed to reduced coverage of oxygenated species on surface Pt sites as evidenced by the positive shift in the onset voltage for OH adsorption.
National Science Foundation (U.S.) (MRSEC under the award number DMR - 0819762)
United States. Dept. of Energy (grant number DE-AC02-98CH10886 through Brookhaven National Laboratory)
Samsung Foundation (Culture)