Investigation of Field-Assisted Surface Chemistry by Atom Probe Tomography
EMSL Project ID
60208
Abstract
Addressing the negative impact of CO2 on the global environment requires a multifaceted mitigation strategy which includes CO2 conversion to higher value compounds, satisfying both economic and environmental concerns. CO2 conversion by catalytic hydrogenation, using hydrogen sourced from renewable sources of energy, appears as an ideal solution. Metallic Nanoparticles (NPs) such as Fe, Co or Platinum Group Metals (PGMs) (Ru, Pd, Pt and Rh) are promising materials for CO2 catalytic transformation into higher value long-chain hydrocarbons. However, developing a catalyst material system with a practical reaction efficiency at is economically viable (e.g. using non-precious metal) requires a fundamental understanding of the reaction steps on the catalyst nanoparticles down to the molecular level to atomic level. More specifically, it is necessary to study the synergistic effect of the catalyst surface and subsurface structure with reactive gases to ultimately design effective and efficient catalytic systems. On approach to alter the thermodynamics of such chemical reactions, in much the same way as temperature and pressure, is through the application of high electric fields. The Atom Probe available in EMSL is a unique tool combining in situ and operando capabilities allowing one to image, at the molecular scale, the effect of reactive gases on the composition and structure of catalytic metal surfaces shaped as a sharp needle, the apex shape of which represents a model nanoparticle morphology. Moreover, this unique tool opens the opportunity to study electric field effect on those surface chemistry mechanisms and explore the opportunities to use electro-catalysis solutions. The hypothesis central to this proposal is that electric field can enhance CO2, CO and O2 hydrogenation over transition metals nanoparticles resulting in both surface AND subsurface structural changes to the catalyst. The field effect would induce a supposed increased local pressure, local temperature and change the metallic surface properties to possibly mimic the noble metal with transition metals. Our goals at EMSL are to use APT, ETEM and high computing to study CO2, CO and O2 hydrogenation and resulting effects over Co and Fe. This work will also result in developing an innovative new technique analytical technique using APT and existing catalyst reactor to study surface chemistry. These results will support theoretical studies at WSU to evaluate the impact of the field effect translated into a temperature/pressure equivalent.
Project Details
Start Date
2021-10-01
End Date
2022-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members