Paolo Longo, Ph.D., Gatan, Inc.
Sample courtesy of Professor Gianluigi Botton at CCEM, Hamilton, ON, Canada
Microscope courtesy of CCEM, Hamilton, ON, Canada
Acknowledgement to Dr. M. Bugnet at CCEM for helping set up microscope for experiment.
EELS color map of a Pt/Fe catalyst nanoparticle
Pt/Fe nanocatalysts are among the most promising candidates for accelerating oxygen reduction reaction occurring at the cathode in a proton exchange membrane fuel cell.
Methods
Probe and image corrected FEI Titan TEM/STEM microscope; X-FEG emission gun; GIF Quantum® ERS system; Fe L2,3-edges at 708 eV (green), Pt M4,5-edges at 2120 eV (red), and O K-edge at 532 eV (blue); voltage: 300 kV; STEM mode; EELS core-loss spectrum (50 – 2500 eV) exposure time: 5 ms; convergence angle: 19 mrad; collection angle: 34 mrad; beam current: 180 pA; dataset size: 426 x 443 pixels