Ultrafast vibrational dynamics of small molecules on platinum (Pt) layers in water are investigated using 2D attenuated total reflectance IR spectroscopy. Isotope combinations of carbon monoxide and cyanide are used to elucidate inter-adsorbate and substrate-adsorbate interactions. Despite observed cross-peaks in the CO spectra, we conclude that the molecules are not vibrationally coupled. Rather, strong substrate-adsorbate interactions evoke rapid (∼2 ps) vibrational relaxation from the adsorbate into the Pt layer, leading to thermal cross-peaks. In the case of CN, vibrational relaxation is significantly slower (∼10 ps) and dominated by adsorbate-solvent interactions, while the coupling to the substrate is negligible.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5367089 | PMC |
http://dx.doi.org/10.1063/1.4978894 | DOI Listing |
ACS Appl Mater Interfaces
November 2024
Institute of Chemistry, The Hebrew University, Jerusalem 91904, Israel.
Fluorinated self-assembled monolayers (SAMs) have been utilized in a variety of applications such as transistors and optoelectronic devices. However, in most SAMs the fluorinated groups could not be positioned in high proximity to the surface due to steric effects. This limitation hinders the direct analysis of the impact of the fluorination level on surface properties.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2024
Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Vietnam.
The CO conversion to methanol (CO-to-CHOH conversion) is a promising way to resolve greenhouse gas emissions and global energy shortage. Many catalysts are of interest in improving the efficiency of the conversion reaction. The PdCo alloy is a potential catalyst, but no research is available to clarify the CO-to-CHOH reaction mechanism of this alloy.
View Article and Find Full Text PDFJ Am Chem Soc
September 2022
Hefei National Research Center for Physical Sciences at the Microscale, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China.
Learning microscopic properties of a material from its macroscopic measurables is a grand and challenging goal in physical science. Conventional wisdom is to first identify material structures exploiting characterization tools, such as spectroscopy, and then to infer properties of interest, often with assistance of theory and simulations. This indirect approach has limitations due to the accumulation of errors from retrieving structures from spectral signals and the lack of quantitative structure-property relationship.
View Article and Find Full Text PDFJ Am Chem Soc
December 2021
Department of Materials Science & Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yeseong-gu, Daejeon 34141, Republic of Korea.
Herein, we report the adsorbate behavior in individual local pores of MIL-101, which is a metal-organic framework (MOF) with two heterogeneous mesopores and different metal sites, by combining adsorbate isotherms and crystallography profiles. The mapping shows that the substrate-adsorbate interaction affects the initial adsorption and pore condensation steps. The monolayer adsorption gradient changes greatly depending on the framework metal-adsorbate attraction force.
View Article and Find Full Text PDFJ Phys Condens Matter
July 2020
Surface Science Research Centre and Department of Physics, University of Liverpool, Liverpool, L69 3BX, United Kingdom.
Metal adsorption upon the 3-fold and 5-fold symmetric surfaces of the i-Ag-In-Yb quasicrystal has led to the observation of unique growth modes. Here, we present a study of the growth of Pb upon the 2-fold i-Ag-In-Yb surface, where the growth mechanism is found to be different from those observed on the other, higher symmetry surfaces of the same system. Initial Pb atoms occupy non-chemically-specific surface sites before forming a row structure.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!