Chaykina Diana, Usman Ismene, Colombi Giorgio, Schreuders Herman, Tyburska-Pueschel Beata, Wu Ziying, Eijt Stephan W H, Bannenberg Lars J, de Wijs Gilles A, Dam Bernard
Materials for Energy Conversion and Storage, Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, NL-2629HZ Delft, The Netherlands.
Dutch Institute for Fundamental Energy Research, De Zaale 20, NL-5612 AJ Eindhoven, The Netherlands.
J Phys Chem C Nanomater Interfaces. 2022 Sep 1;126(34):14742-14749. doi: 10.1021/acs.jpcc.2c04456. Epub 2022 Aug 19.
To develop an understanding of the photochromic effect in rare-earth metal oxyhydride thin films (REH O , here RE = Y), we explore the aliovalent doping of the RE cation. We prepared Ca-doped yttrium oxyhydride thin films ((Ca Y )H O ) 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.
为了深入理解稀土金属氢氧化物薄膜（REHₓOᵧ，此处RE = Y）中的光致变色效应，我们研究了稀土阳离子的异价掺杂。我们通过反应磁控共溅射制备了钙掺杂的氧化钇氢化物薄膜（(CaₓY₁₋ₓ)HₓOᵧ），钙掺杂浓度在0至36原子百分比之间。对于钙含量低于15%的所有薄膜，它们均为具有恒定光学带隙的半导体，而对于高于15%的成分，带隙会扩大。钙掺杂会影响光致变色性能，导致（1）光致变色对比度降低，这可能是由于氢浓度较低所致，以及（2）漂白速度加快，这是由较高的指前因子引起的。总体而言，这些结果表明氢浓度对于“变暗”相形成的重要性以及这些氢的局部重排对于该过程动力学的重要性。
