ab initio Quantum Calculations of 195Pt Knight Shifts in Pt-based Bimetallic Nanoparticles
EMSL Project ID
34935
Abstract
Nanoscale catalysts are of considerable importance in a number of industrially and environmentally applications of heterogeneous catalysis. Platinum-based bimetallic nanoparticles are the most widely used catalysts in industrial processes with applications in diverse areas such as petrochemical refineries, pharmaceuticals and fuel cells. In order to improve the development of these catalysts, an in situ method for chemical and physical characterization of nanoparticle catalysts is needed. The present proposal addresses the problem through the development of a spatially and temporally resolved 195Pt NMR spectroscopic technique. The proposed work involves the use of EMSL computing facilities to support ab initio quantum chemistry calculations of the 195Pt Knight shift in Pt-based bimetallic nanoparticles. These calculations will be used in the deconvolution and interpretation of 195Pt NMR experiments performed at Georgetown University. X-ray photoelectron spectroscopy (XPS) experiments will be performed at the National Institute of Standards and Technology.Computations based on density functional theory (DFT) have been very successful in attacking a wide range of problems in chemistry, materials science and solid state physics. It is proposed to perform DFT calculations on a family of Pt-based bimetallic clusters of increasing size. As most calculations of NMR shifts to date have been made on the bulk slab, the proposed calculations on the nanoparticle itself should represent a considerable improvement over the traditional approach. Indeed, initial results based on small nanoparticles are encouraging.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2009-10-01
End Date
2012-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Allison TC, and YJ Tong. 2011. "Evaluation of Methods to Predict Reactivity of Gold Nanoparticles." Physical Chemistry Chemical Physics. PCCP 13:12858–12864. doi:10.1039/c1cp20376b
Park IS, B Xu, DO Atienza, AM Hofstead-Duffy, TC Allison, and YJ Tong. 2011. "Chemical State of Adsorbed Sulfur on Pt Nanoparticles." Chemphyschem 12(4):747-752. doi:10.1002/cphc.201000998
Zaluzhna O, L Brightful, TC Allison, and YJ Tong. 2011. "Spectroscopic Evidence of a Bidentatebidentate-Binding of Meso-2,3-Dimercaptosuccinic Acid on Silver Nanoclusters." Chemical Physics Letters 509(4-6):148-151. doi:10.1016/j.cplett.2011.04.087