Orbital Engineering in Three Dimensional Halide Perovskites towards Two Dimensional Properties with Strong Anisotropy
arXiv:1907.09879 · doi:10.1021/acs.jpclett.9b02530
Abstract
The discovery of double perovskites A2B(I)B(III)X6 (A=monovalent cation; B(I)/B(III) = metal cation; X = halogen) as Pb(II)-free alternatives has attracted widespread attention, making it possible to introduce d-block metal cations (e.g., d0 and d10) into halide perovskites. However, at present, there are quite limited insights into the underlying bonding orbitals for d-block metal cation-based halide perovskites. Here, we present an orbital engineering strategy to construct two-dimensional (2D) electronic structures in three-dimensional (3D) halide perovskites by rationally controlling the d orbitals of the metal cations to hybridize with the halide p orbitals. Taking Cs2Au(I)Au(III)I6 as an example, we demonstrate that the flat conduction band and valence band at the band edges can be achieved simultaneously by combining two metal cations with different d orbital configurations using the first-principles calculations. The predicted carrier mobilities show huge anisotropy along the in-plane and out-of-plane directions in Cs2Au(I)Au(III)I6, further confirming the 2D electronic properties. In addition, the anisotropic static dielectronic constants and Young's modulus are also observed. More importantly, it is found that Cs2Au(I)Au(III)I6 has excellent mechanical flexible and an ultra-small shear modulus among halide perovskites. Our work provides valuable guidance for achieving low-dimensional electronic characteristic in three-dimensional halide perovskites for novel electronic applications.
References in corpus (10)
- Design of Lead-Free Inorganic Halide Perovskites for Solar Cells via Cation-Transmutation
- Parity-Forbidden Transitions and Their Impacts on the Optical Absorption Properties of Lead-Free Metal Halide Perovskites and Double Perovskites
- Structural and Electronic Properties of Hybrid Perovskites for High-Efficiency Thin-Film Photovoltaics from First-Principles
- Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices
- Low-Dimensional Transport and Large Thermoelectric Power Factors in Bulk Semiconductors by Band Engineering of Highly Directional Electronic States
- Hexagonal Rare-Earth Manganites as Promising Photovoltaics and Light Polarizers
- Dielectric Behavior as a Screen in Rational Searches for Electronic Materials: Metal Pnictide Sulfosalts
- Mechanical Properties of Formamidinium Halide Perovskites FABX3 (FA = CH(NH2)2; B = Pb, Sn; X = Br, I) From First-Principles
- Large birefringence and linear dichroism in TiS3 nanosheets
- Orbital engineering in nickelate heterostructures driven by anisotropic oxygen hybridization rather than orbital energy levels