Observation of surface structure of Platinum catalyst with various modes FE-SEM

Abstract number
690
Event
European Microscopy Congress 2020
DOI
10.22443/rms.emc2020.690
Corresponding Email
[email protected]
Session
PSA.5 - Nanoparticles & Catalysts
Authors
Ji Hee Kwon (1), So Hee Kim (1), Go-Woon Lee (1), Kwangshik Myung (1)
Affiliations
1. Korea Institute of Energy Research (KIER)
Keywords

FE-SEM, Triple detectors, Platinum catalyst

Abstract text

Recent progress of Field Emission Scanning Electron Microscope (FE-SEM) technology makes it possible to observe the sample of ultra-high resolution imaging even at low accelerating voltage. Also it enable us to see a variety of high quality composition images by using the triple detector system(Top, Upper, Lower). Especially, with the top detector additional signal collection is possible. So triple detectors provide a variety of signal collection and there are suitable for many imaging applications such as SE, HA-BSE, LA-BSE images.

 

Platinum catalyst  (Pt nanoparticles on the carbon support) is the most commonly used one of precious metal catalyst and it has an important role in polymer electrolyte membrane fuel cells (PEMFCs).

However, the high cost of platinum catalyst has become a major obstacle to the commercialization of PEMFCs. So it has been under intensive study about the low Pt-loading carbon supported catalysts. 

 

In this work, FE-SEM observation using the triple detector system allow us to image the surface structure of Platinum catalyst. We attempted to compare the obtained images using each detector. A commercial catalyst of 50 wt.% Pt/C is used as the sample. For sample preparation we attached the sample to a carbon tape and all observation was carried out without a metal coating at low acceleration voltages (2 kV) using a HITACHI Regulus 8220 FE-SEM.

 

As a result, we can see a little different image using each detector. Top detector can detect High angle BSE (HA-BSE), which offers rich compositional information. SE and Low angle BSE (LA-BSE) are detected with the Upper detector. The Se signal for surface topography and the LA-BSE signal for both topographical information and compositional contrast. Topographical information can be emphasized using Lower detector.  

 

This work shows that the application of triple detector system makes it possible to obtain useful information. Also this application can be expected to apply other samples to get interesting results.