Simultaneous measurements of solid–liquid interfaces and bulk liquids using soft X-ray absorption spectroscopy

Simultaneous measurement methods for soft X-ray absorption spectroscopy (XAS) of solid–liquid interfaces and bulk liquids have been developed. The O K -edge XAS spectra of H 2 O/Au interfaces and bulk H 2 O were measured using a transmission-type liquid cell, in which the liquid layer was sandwiched between Au/Cr/Si 3 N 4 and Si 3 N 4 membranes. The XAS spectrum of bulk H 2 O was obtained using the transmission method by controlling the thickness of the liquid layer, whereas the XAS spectrum of the H 2 O/Au interface was obtained using the electron-yield method by measuring the drain currents from the Au surface after soft X-ray absorption. The XAS spectra of bulk H 2 O and the H 2 O/Au interfaces were differentiated to determine the appropriate measurement conditions for the solid–liquid interfaces interfaces.