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Updated: May 20, 2025

Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
Oxygen-Substitution Induced High-Performance Nonlinear Optical Properties: Witnessed by the First Quaternary
Rui Xiao1,2, Wen-Dong Yao3, Wenhao Xing2
1Yunnan Key Laboratory of Electromagnetic Materials and Devices, National Center for International Research on Photoelectric and Energy Materials, School of Material and Energy, Yunnan University, Kunming, 650000, P. R. China.
Abstract:
Oxychalcogenides can combine the large second-harmonic generation (SHG) effects of chalcogenides with the wide bandgaps of oxides to obtain high-performance infrared (IR) nonlinear optical (NLO) crystal materials. Here, the first quaternary oxythiostannate NLO crystal material Sr6Sn3OS11 crystallized in the trigonal noncentrosymmetric space group P3m1 is synthesized by a high-temperature solid-state method. Its 0D structure features isolated [SnS4] and [SnOS3] tetrahedra, which can be derived from parent 0D Sr2SnS4 (Ama2) via anion partial substitution. The SHG response of Sr6Sn3OS11 primarily contributed by [SnS4] tetrahedra is increased to be 0.82 × benchmark AgGaS2 compared with 0.5 × AgGaS2 for Sr2SnS4. The experimental bandgap of Sr6Sn3OS11 is 2.81 eV, which is mainly determined by the Sr 4d and S 3p orbitals according to the theoretical calculation results. This work not only expands oxythiostannates as promising IR NLO materials but also contributes a facile strategy to improve the NLO properties from known ones.
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