Open AccessQuantification of Adsorbates by X-ray Absorption Spectroscopy: Getting TGA-like Information for Free
Author(s) -
Kirill A. Lomachenko,
Anastasia Yu. Molokova,
Cesare Atzori,
Olivier Mathon
Publication year - 2022
Publication title -
journal of physical chemistry. c./journal of physical chemistry. c
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.401
H-Index - 289
eISSN - 1932-7455
pISSN - 1932-7447
DOI - 10.1021/acs.jpcc.2c00226
Subject(s) - x ray absorption spectroscopy , absorption spectroscopy , absorption (acoustics) , extended x ray absorption fine structure , thermogravimetric analysis , chemistry , sorption , spectroscopy , desorption , analytical chemistry (journal) , adsorption , materials science , optics , organic chemistry , physics , quantum mechanics , composite material
Hard X-ray absorption spectroscopy (XAS) is frequently applied in catalysis and gas sorption studies to monitor changes in oxidation states, coordination numbers, and interatomic distances of active sites under in situ and operando conditions. However, transmission XAS data can reveal also the change in the total amount of guest species adsorbed on the whole sample. Surprisingly, to the best of our knowledge, the latter property has never been exploited. Here, we present a simple method to quantify the amount of adsorbates from XAS data collected during the interaction of the sample with gases or liquids. The method relies on monitoring the change of the total absorption level below the measured absorption edge and does not require any additional instrumentation or modification of the XAS data collection procedure. Essentially, it is a way to obtain the information analogous to the one delivered by temperature-programmed reduction (TPR), temperature-programmed desorption (TPD), or thermogravimetric analysis (TGA) directly from XAS at no extra cost.