Speaker
Description
A custom apparatus was developed at I07 Surface and Interface Diffraction beamline, Diamond Light Source (DLS) to perform operando measurements of solid/electrolyte interfaces under external potential and UV illumination using surface X-ray diffraction (SXRD).
Samples can be prepared under ultra-high vacuum (UHV) using standard methods in DLS Surface and Interface Laboratory. Pre-characterisation such as low energy electron diffraction, scanning tunnelling microscopy and X-ray photoelectron spectroscopy (LEED, STM, XPS) can be performed prior to transferring the sample under UHV to the Photo-ElectroChemical DrOplet Cell (PEC-DOC). The PEC-DOC is then transferred and mounted of I07’s EH1 diffractometer for SXRD structure determination under UHV. A custom liquid delivery device comprising a working and reference electrodes is then introduced in the chamber under controlled atmosphere. A droplet of electrolyte is contacted to the surface using an endoscope, also utilised to monitor the shape of the droplet during acquisition.
Using the PEC-DOC, the electrical double layer of the TiO2(110) interface with 0.1 M KCl(aq) has been elucidated. This represents an insight into the behaviour of the semiconductor in a neutral interface to define the structure of the electrical double layer present. The electrochemical capabilities of the PEC-DOC enabled cyclic voltammograms of the surface interface to be recorded. It also allowed a bias voltage to be applied for SXRD measurements, providing a tentative insight into the electrochemical desorption taking place as a result of applied positive potential.
This work was supported by the European Research Council Advanced Grant ENERGYSURF to GT, EPSRC (EP/L015862/1). AW has received funding from the European Union’s research and innovation programme under the Marie Sklodowska-Curie grant GA No 665593.
| I plan to submit also conference proceedings | Yes |
|---|
