Closing the pressure gap in x-ray photoelectron spectroscopy by membrane hydrogenation

摘要: Comprehensive studies of gas-solid reactions require the in-situ interaction gas at a pressure beyond operating ultrahigh vacuum (UHV) X-ray photoelectron spectroscopy (XPS). The recent progress near ambient XPS allows to dose gases sample up 20 mbar. present work describes an alternative this experimental challenge, with focus on H2 as interacting gas. Instead exposing under investigation gaseous hydrogen, is in contact hydrogen permeation membrane, through which transported from outside atomic hydrogen. Thereby, we can reach local concentrations inside UHV chamber, equipped surface science tools, and corresponds 1 bar without affecting sensitivity or energy resolution spectrometer. This approach validated by two examples, that is, reduction catalyst precursor for CO2 hydrogenation water photocatalytic production, but it opens possibility new situ characterisation materials catalysts.