Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published December 16, 2016 | Submitted + Supplemental Material
Journal Article Open

Ultrafine jagged platinum nanowires enable ultrahigh mass activity for the oxygen reduction reaction

Abstract

Improving the platinum (Pt) mass activity for the oxygen reduction reaction (ORR) requires optimization of both the specific activity and the electrochemically active surface area (ECSA). We found that solution-synthesized Pt/NiO core/shell nanowires can be converted into PtNi alloy nanowires through a thermal annealing process and then transformed into jagged Pt nanowires via electrochemical dealloying. The jagged nanowires exhibit an ECSA of 118 square meters per gram of Pt and a specific activity of 11.5 milliamperes per square centimeter for ORR (at 0.9 volts versus reversible hydrogen electrode), yielding a mass activity of 13.6 amperes per milligram of Pt, nearly double previously reported best values. Reactive molecular dynamics simulations suggest that highly stressed, undercoordinated rhombus-rich surface configurations of the jagged nanowires enhance ORR activity versus more relaxed surfaces.

Additional Information

© 2016 American Association for the Advancement of Science. Received 18 April 2016; resubmitted 25 August 2016. Accepted 26 October 2016; Published online 17 November 2016. Supported by DOE Office of Basic Energy Sciences, Division of Materials Science and Engineering, award DE-SC0008055 (X.D., M.L., and Z.L. for materials synthesis and characterizations); NSF grant CHE-1508692 (Y.H., Z.Z., and E.Z. for electrochemical studies); NSF grant CBET-1512759 (W.A.G., A.F., B.V.M., and T.C. for theoretical computations); and National Natural Science Foundation of China project numbers 51525102, 51390475, and 51371102 (R.Y. for STEM studies). The Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences, of DOE under contract DE-AC02-05CH11231. We thank M. A. Marcus for support during the acquisition of XAS data and C. Wu for help with EXAFS data analysis. The aberration-corrected TEM results were achieved (in part) using Titan 80-300 and JEM-ARM 200F. In this work we used the resources of the National Center for Electron Microscopy in Beijing. A patent application on this subject has been filed [UC case no. 2017-108-1-LA (102352-0512)].

Attached Files

Submitted - Li.SM.pdf

Supplemental Material - Science-JPtNW-Huang-Oct14-wag.pdf

Files

Li.SM.pdf
Files (10.4 MB)
Name Size Download all
md5:c6bcf18cc1b8453c6017487d3d7d5a8c
3.4 MB Preview Download
md5:02bc29350b9153018f9b9d07d4208386
7.0 MB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 23, 2023