Kinetics, Energetics, and Size Dependence of the Transformation from Pt to Ordered PtSn Intermetallic Nanoparticles

Thumbnail Image
Supplemental Files
Date
2019-01-01
Authors
Chen, Minda
Han, Yong
Goh, Tian Wei
Sun, Rong
Maligal‐Ganesh, Raghu
Pei, Yuchen
Tsung, Chia‐ Kuang
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Authors
Person
Evans, James
Professor
Person
Huang, Wenyu
Professor
Research Projects
Organizational Units
Organizational Unit
Ames National Laboratory

Ames National Laboratory is a government-owned, contractor-operated national laboratory of the U.S. Department of Energy (DOE), operated by and located on the campus of Iowa State University in Ames, Iowa.

For more than 70 years, the Ames National Laboratory has successfully partnered with Iowa State University, and is unique among the 17 DOE laboratories in that it is physically located on the campus of a major research university. Many of the scientists and administrators at the Laboratory also hold faculty positions at the University and the Laboratory has access to both undergraduate and graduate student talent.

Organizational Unit
Physics and Astronomy
Physics and astronomy are basic natural sciences which attempt to describe and provide an understanding of both our world and our universe. Physics serves as the underpinning of many different disciplines including the other natural sciences and technological areas.
Organizational Unit
Chemistry

The Department of Chemistry seeks to provide students with a foundation in the fundamentals and application of chemical theories and processes of the lab. Thus prepared they me pursue careers as teachers, industry supervisors, or research chemists in a variety of domains (governmental, academic, etc).

History
The Department of Chemistry was founded in 1880.

Dates of Existence
1880-present

Related Units

Journal Issue
Is Version Of
Versions
Series
Abstract

The outstanding catalytic activity and chemical selectivity of intermetallic compounds make them excellent candidates for heterogeneous catalysis. However, the kinetics of their formation at the nanoscale is poorly understood or characterized, and precise control of their size, shape as well as composition during synthesis remains challenging. Here, using well-defined Pt nanoparticles (5 nm and 14 nm) encapsulated in mesoporous silica, we study the transformation kinetics from monometallic Pt to intermetallic PtSn at different temperatures by a series of time-evolution X-ray diffraction studies. Observations indicate an initial transformation stage mediated by Pt surface-controlled intermixing kinetics, followed by a second stage with distinct transformation kinetics corresponding to a Ginstling-Brounstein (G-B) type bulk diffusion mode. Moreover, the activation barrier for both surface intermixing and diffusion stages are obtained through the development of appropriate kinetic models for analysis of experimental data. Our density-functional-theory (DFT) calculations provide further insights into the atomistic-level processes and associated energetics underlying surface-controlled intermixing.

Comments

This is article is published as Chen, Minda, Yong Han, Tian Wei Goh, Rong Sun, Raghu V. Maligal-Ganesh, Yuchen Pei, Chia-Kuang Frank Tsung, James Evans, and Wenyu Huang. "Kinetics, Energetics, and Size Dependence of the Transformation from Pt to Ordered PtSn Intermetallic Nanoparticles." Nanoscale 11 (2019): 5336. DOI: 10.1039/C8NR10067E. Posted with permission.

Description
Keywords
Citation
DOI
Copyright
Tue Jan 01 00:00:00 UTC 2019
Collections