Highly Distorted Chiral Two-Dimensional Tin Iodide Perovskites for Spin Polarized Charge Transport
| Autor: | Chuanxiao Xiao, Joseph J. Berry, David B. Mitzi, Andrew Levin, Matthew C. Beard, Ruyi Song, Annalise E. Maughan, Haipeng Lu, Tianyang Li, Roman Brunecky, Volker Blum |
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| Rok vydání: | 2020 |
| Předmět: |
chemistry.chemical_classification
Band gap business.industry Iodide chemistry.chemical_element General Chemistry 010402 general chemistry 01 natural sciences Biochemistry Catalysis 0104 chemical sciences Crystallography Colloid and Surface Chemistry Semiconductor chemistry Octahedron Phase (matter) Electronic band structure Tin business Perovskite (structure) |
| Zdroj: | Journal of the American Chemical Society. 142(30) |
| ISSN: | 1520-5126 |
| Popis: | Incorporating chiral organic molecules into organic/inorganic hybrid 2D metal-halide perovskites results in a novel family of chiral hybrid semiconductors with unique spin-dependent properties. The embedded chiral organic moieties induce a chiroptical response from the inorganic metal-halide sublattice. However, the structural interplay between the chiral organic molecules and the inorganic sublattice, as well as their synergic effect on the resulting electronic band structure need to be explored in a broader material scope. Here we present three new layered tin iodide perovskites templated by chiral (R/S-)methylbenzylammonium (R/S-MBA), i.e., (R-/S-MBA)2SnI4, and their racemic phase (rac-MBA)2SnI4. These MBA2SnI4 compounds exhibit the largest level of octahedral bond distortion compared to any other reported layered tin iodide perovskite. The incorporation of chiral MBA cations leads to circularly polarized absorption from the inorganic Sn-I sublattice, displaying chiroptical activity in the 300-500 nm wavelength range. The bandgap and chiroptical activity are modulated by alloying Sn with Pb, in the series of (MBA)2Pb1-xSnxI4. Finally, we show that vertical charge transport through oriented (R-/S-MBA)2SnI4 thin films is highly spin-dependent, arising from a chiral-induced spin selectivity (CISS) effect. We demonstrate a spin-polarization in the current-voltage characteristics as high as 94%. Our work shows the tremendous potential of these chiral hybrid semiconductors for controlling both spin and charge degrees of freedom. |
| Databáze: | OpenAIRE |
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