title: High-Pressure Study of Perovskite-Like Organometal Halide: Band-Gap Narrowing and Structural Evolution of [NH3-(CH2)4-NH3]CuCl4.
abstract: Searching for nontoxic and stable perovskite-like alternatives to lead-based halide perovskites for photovoltaic application is one urgent issue in photoelectricity science. Such exploration inevitably requires an effective method to accurately control both the crystalline and electronic structures. This work applies high pressure to narrow the band gap of perovskite-like organometal halide, [NH3-(CH2)4-NH3]CuCl4(DABCuCl4), through the crystalline-structure tuning. The band gap keeps decreasing below ∼12 GPa, involving the shrinkage and distortion of CuCl42-. Inorganic distortion determines both band-gap narrowing and phase transition between 6.4 and 10.5 GPa, and organic chains function as the spring cushion, evidenced by the structural transition at ∼0.8 GPa. The supporting function of organic chains protects DABCuCl4from phase transition and amorphization, which also contributes to the sustaining band-gap narrowing. This work combines crystal structure and macroscopic property together and offers new strategies for the further design and synthesis of hybrid perovskite-like alternatives.
authors.affiliation: State Key Laboratory of Superhard Materials, Jilin University , Changchun 130012, China.|Department of Chemistry, South University of Science and Technology of China , Shenzhen, Guangdong 518055, China.|High Pressure Collaborative Access Team (HPCAT), Geophysical Laboratory, Carnegie Institution of Washington , Argonne, Illinois 60439, United States.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy Of Engineering Physics , Mianyang 621900, China.
authors.forename: Shourui
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Superhard Materials, Jilin University , Changchun 130012, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Chemistry, South University of Science and Technology of China , Shenzhen, Guangdong 518055, China.
authors.forename: Zewei
authors.initials: Z
authors.lastname: Quan
authors.affiliation: High Pressure Collaborative Access Team (HPCAT), Geophysical Laboratory, Carnegie Institution of Washington , Argonne, Illinois 60439, United States.
authors.forename: Yue
authors.initials: Y
authors.lastname: Meng
authors.affiliation: State Key Laboratory of Superhard Materials, Jilin University , Changchun 130012, China.
authors.forename: Bo
authors.identifier: http://orcid.org/0000-0002-3215-1255
authors.initials: B
authors.lastname: Zou