Hybrid Germanium Bromide Perovskites with Tunable Second Harmonic Generation

Yang Liu; Ya-Ping Gong; Shining Geng; Mei-Ling Feng; Despoina Manidaki; Zeyu Deng; Constantinos C Stoumpos; Pieremanuele Canepa; Zewen Xiao; Wei-Xiong Zhang; Lingling Mao

doi:10.1002/anie.202208875

Hybrid Germanium Bromide Perovskites with Tunable Second Harmonic Generation

Angew Chem Int Ed Engl. 2022 Oct 24;61(43):e202208875. doi: 10.1002/anie.202208875. Epub 2022 Sep 21.

Authors

Affiliations

¹ Department of Chemistry, SUSTech Energy Institute for Carbon Neutrality, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, P. R. China.
² MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, P. R. China.
³ Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, P. R. China.
⁴ State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, P. R. China.
⁵ Department of Materials Science and Technology, University of Crete, Heraklion, 70013, Greece.
⁶ Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore.
⁷ Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117585, Singapore.

PMID: 36043492
DOI: 10.1002/anie.202208875

Abstract

Ge-based hybrid perovskite materials have demonstrated great potential for second harmonic generation (SHG) due to the geometry and lone-pair induced non-centrosymmetric structures. Here, we report a new family of hybrid 3D Ge-based bromide perovskites AGeBr₃ , A=CH₃ NH₃ (MA), CH(NH₂ )₂ (FA), Cs and FAGe_0.5 Sn_0.5 Br₃ , crystallizing in polar space groups. These compounds exhibit tunable SHG responses, where MAGeBr₃ shows the strongest SHG intensity (5×potassium dihydrogen phosphate, KDP). Structural and theoretical analysis indicate the high SHG efficiency is attributed to the displacement of Ge²⁺ along [111] direction and the relatively strong interactions between lone pair electrons of Ge²⁺ and polar MA cations along the c-axis. This work provides new structural insights for designing and fine-tuning the SHG properties in hybrid metal halide materials.

Keywords: Halide Perovskites; Non-Centrosymmetric Structure; Non-Linear Optics; Second Harmonic Generation.

Grants and funding

Y01216150/Southern University of Science and Technology