Roles of spin-orbit coupling in tetragonal hybrid halide perovskite for photovoltaics light-absorber

Cs2AuBiCl6 is considered to be a potential lead‐free double perovskite alternative for perovskite solar cells. Its electronic and optical properties are investigated using density functional theory. The electronic properties of Cs2AuBiCl6 material ensure a bandgap of 1.40 eV (without considering SOC) and 1.12 eV (with SOC) using mBJ exchange‐correlation functional, close to the optimal bandgap for solar cell application as per the Shockley–Queisser limit. Optical properties suggest a high absorption coefficient ≈105 cm−1 with low reflectance, making it the optimal absorber material. Furthermore, the photovoltaic performance of Cs2AuBiCl6 based single‐junction transparent conducting oxide (TCO)/IDL1/Cs2AuBiCl6/IDL2/Cu2O solar cell is investigated using SCAPS‐1D device simulation program. The impact of electron affinity, thickness, carrier concentration, defect density, and interface defect density is examined using interface defect layer (IDL) on the photovoltaic performance. The maximum photoconversion efficiency (PCE) of ≈22.18% is noticed for optimized material's parameters. These studies on TCO/IDL1/Cs2AuBiCl6/IDL2/Cu2O solar cell will provide guidelines for designing and developing an efficient lead‐free perovskite‐based solar cell as an alternative to conventional halide perovskite materials based solar cell.

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“…The result is also in agreement with the already reported SOC results on other perovskites. [ 36,37 ]…”

Section: Resultsmentioning

confidence: 99%

Inorganic Lead‐Free Cs₂AuBiCl₆ Perovskite Absorber and Cu₂O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency

Kale

Chaurasiya

Dixit

2021

Advcd Theory and Sims

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“…This is because SOC does not cause any splitting of either of the band extrema, although the magnitude E g is affected. The decrease in the magnitude of the E g due to SOC can be as large as 1 eV 94,101 , which is due to the degenerate (empty) 6p orbitals that are split and shifted apart in energy. This attribute has been referred to as a structure-dependent SOC response, which is enhanced for less tilted structures leading to an effective bandgap reduction 102 .…”

Section: Methodsmentioning

confidence: 99%

Significance of hydrogen bonding and other noncovalent interactions in determining octahedral tilting in the CH3NH3PbI3 hybrid organic-inorganic halide perovskite solar cell semiconductor

Varadwaj

Marques

Yamashita

2019

Sci Rep

116

100

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The CH3NH3PbI3 (methylammonium lead triiodide) perovskite semiconductor system has been viewed as a blockbuster research material during the last five years. Because of its complicated architecture, several of its technological, physical and geometrical issues have been examined many times. Yet this has not assisted in overcoming a number of problems in the field nor in enabling the material to be marketed. For instance, these studies have not clarified the nature and type of hydrogen bonding and other noncovalent interactions involved; the origin of hysteresis; the actual role of the methylammonium cation; the nature of polarity associated with the tetragonal geometry; the unusual origin of various frontier orbital contributions to the conduction band minimum; the underlying phenomena of spin-orbit coupling that causes significant bandgap reduction; and the nature of direct-to-indirect bandgap transition features. Arising from many recent reports, it is now a common belief that the I···H–N interaction formed between the inorganic framework and the ammonium group of CH3NH3+ is the only hydrogen bonded interaction responsible for all temperature-dependent geometrical polymorphs of the system, including the most stable one that persists at low-temperatures, and the significance of all other noncovalent interactions has been overlooked. This study focussed only on the low temperature orthorhombic polymorph of CH3NH3PbI3 and CD3ND3PbI3, where D refers deuterium. Together with QTAIM, DORI and RDG based charge density analyses, the results of density functional theory calculations with PBE with and without van der Waals corrections demonstrate that the prevailing view of hydrogen bonding in CH3NH3PbI3 is misleading as it does not alone determine the a−b+a− tilting pattern of the PbI64− octahedra. This study suggests that it is not only the I···H/D–N, but also the I···H/D–C hydrogen/deuterium bonding and other noncovalent interactions (viz. tetrel-, pnictogen- and lump-hole bonding interactions) that are ubiquitous in the orthorhombic CH3NH3PbI3/CD3ND3PbI3 perovskite geometry. Their interplay determines the overall geometry of the polymorph, and are therefore responsible in part for the emergence of the functional optical properties of this material. This study also suggests that these interactions should not be regarded as the sole determinants of octahedral tilting since lattice dynamics is known to play a critical role as well, a common feature in many inorganic perovskites both in the presence and the absence of the encaged cation, as in CsPbI3/WO3 perovskites, for example.

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“…Notably, R -MBA and S -MBA molecules in solution show CD signals at 259 nm. The fact that CD signals exist at wavelengths corresponding to the band edge of perovskite suggests that chirality is transferred to a perovskite structure that changed the electronic structure of perovskite semiconductors . Samples with Sn concentrations of 5% and 10% show high CD values, which are comparable to their Pb analogue.…”

Section: Synthesis Of Chiral Perovskite Filmsmentioning

confidence: 99%

Symmetry-Broken 2D Lead–Tin Mixed Chiral Perovskite for High Asymmetry Factor Circularly Polarized Light Detection

et al. 2023

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Symmetry-broken-induced spin splitting plays a key role for selective circularly polarized light absorption and spin carrier transport. Asymmetrical chiral perovskite is rising as the most promising material for direct semiconductor-based circularly polarized light detection. However, the increase of asymmetry factor and extension of response region remain to be a challenge. Herein, we fabricated a two-dimensional tin−lead mixed chiral perovskite with tunable absorption in the visible region. Theoretical simulation indicates that the mixing of the tin and lead in chiral perovskite breaks the symmetry of the pure ones, resulting in pure spin splitting. We then fabricated a chiral circularly polarized light detector based on this tin−lead mixed perovskite. A high asymmetry factor for the photocurrent of 0.44 is achieved, which is 144% higher than pure lead 2D perovskite, and it is the highest value reported for the pure chiral 2D perovskite-based circularly polarized light detector using a simple device structure.

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Roles of spin-orbit coupling in tetragonal hybrid halide perovskite for photovoltaics light-absorber

Cited by 9 publications

References 19 publications

Inorganic Lead‐Free Cs₂AuBiCl₆ Perovskite Absorber and Cu₂O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency

Inorganic Lead‐Free Cs₂AuBiCl₆ Perovskite Absorber and Cu₂O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency

Significance of hydrogen bonding and other noncovalent interactions in determining octahedral tilting in the CH3NH3PbI3 hybrid organic-inorganic halide perovskite solar cell semiconductor

Symmetry-Broken 2D Lead–Tin Mixed Chiral Perovskite for High Asymmetry Factor Circularly Polarized Light Detection

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Roles of spin-orbit coupling in tetragonal hybrid halide perovskite for photovoltaics light-absorber

Cited by 9 publications

References 19 publications

Inorganic Lead‐Free Cs2AuBiCl6 Perovskite Absorber and Cu2O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency

Inorganic Lead‐Free Cs2AuBiCl6 Perovskite Absorber and Cu2O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency

Significance of hydrogen bonding and other noncovalent interactions in determining octahedral tilting in the CH3NH3PbI3 hybrid organic-inorganic halide perovskite solar cell semiconductor

Symmetry-Broken 2D Lead–Tin Mixed Chiral Perovskite for High Asymmetry Factor Circularly Polarized Light Detection

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Product

Resources

About

Inorganic Lead‐Free Cs₂AuBiCl₆ Perovskite Absorber and Cu₂O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency

Inorganic Lead‐Free Cs₂AuBiCl₆ Perovskite Absorber and Cu₂O Hole Transport Material Based Single‐Junction Solar Cells with 22.18% Power Conversion Efficiency