Influence of Cation (RE = Sc, Y, Gd) and O/H Anion Ratio on the Photochromic Properties of REOxH3-2x Thin Films

Journal article (2021)

Authors

G. Colombi ChemE/Materials for Energy Conversion and Storage - AS
Tom De Krom Student
D. Chaykina ChemE/Materials for Energy Conversion and Storage - AS
S. Cornelius ChemE/Materials for Energy Conversion and Storage - AS
S.W.H. Eijt RST/Fundamental Aspects of Materials and Energy - AS
B. Dam ChemE/Chemical Engineering
Research Group
ChemE/Materials for Energy Conversion and Storage (AS) (TU Delft)
Copyright: © 2021 G. Colombi, Tom De Krom, D. Chaykina, S. Cornelius, S.W.H. Eijt, B. Dam
DOI: https://doi.org/10.1021/acsphotonics.0c01877
More Info
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Published Date

2021

Language

English

Faculty

Applied Sciences

Department

ChemE/Chemical Engineering

Research Group

ChemE/Materials for Energy Conversion and Storage

Abstract

Rare-earth oxyhydride REOxH3-2x thin films prepared by air-oxidation of reactively sputtered REH2 dihydrides show a color-neutral, reversible photochromic effect at ambient conditions. The present work shows that the O/H anion ratio, as well as the choice of the cation, allow to largely tune the extent of the optical change and its speed. The bleaching time, in particular, can be reduced by an order of magnitude by increasing the O/H ratio, indirectly defined by the deposition pressure of the parent REH2. The influence of the cation (RE = Sc, Y, Gd) under comparable deposition conditions is discussed. Our data suggest that REs of a larger ionic radius form oxyhydrides with a larger optical contrast and faster bleaching speed, hinting to a dependency of the photochromic mechanism on the anion site-hopping.