Aliovalent Calcium Doping of Yttrium Oxyhydride Thin Films and Implications for Photochromism

Journal article (2022)

Authors

D. Chaykina ChemE/Materials for Energy Conversion and Storage - AS
I.N. Usman QN/Kavli Nanolab Delft - AS
G. Colombi ChemE/Materials for Energy Conversion and Storage - AS
H. Schreuders ChemE/O&O groep - AS
Beata Tyburska-Pueschel Dutch Institute for Fundamental Energy Research
Z. Wu RST/Fundamental Aspects of Materials and Energy - AS
S.W.H. Eijt RST/Fundamental Aspects of Materials and Energy - AS
L.J. Bannenberg RID/TS/Instrumenten groep , RST/Storage of Electrochemical Energy - AS
Gilles A. De Wijs Radboud Universiteit Nijmegen
B. Dam ChemE/Chemical Engineering
Research Group
ChemE/Materials for Energy Conversion and Storage (AS) (TU Delft)
Copyright: © 2022 D. Chaykina, I.N. Usman, G. Colombi, H. Schreuders, Beata Tyburska-Pueschel, Z. Wu, S.W.H. Eijt, L.J. Bannenberg, Gilles A. De Wijs, B. Dam
DOI: https://doi.org/10.1021/acs.jpcc.2c04456
More Info
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Published Date

2022

Language

English

Faculty

Applied Sciences

Department

ChemE/Chemical Engineering

Research Group

ChemE/Materials for Energy Conversion and Storage

Abstract

To develop an understanding of the photochromic effect in rare-earth metal oxyhydride thin films (REH3-2xOx, here RE = Y), we explore the aliovalent doping of the RE cation. We prepared Ca-doped yttrium oxyhydride thin films ((CazY1-z)HxOy) by reactive magnetron cosputtering with Ca doping concentrations between 0 and 36 at. %. All of the films are semiconductors with a constant optical band gap for Ca content below 15%, while the band gap expands for compositions above 15%. Ca doping affects the photochromic properties, resulting in (1) a lower photochromic contrast, likely due to a lower H- concentration, and (2) a faster bleaching speed, caused by a higher pre-exponential factor. Overall, these results point to the importance of the H- concentration for the formation of a "darkened"phase and the local rearrangement of these H- for the kinetics of the process.