Computational Study of Structural and Electronic Properties of Lead

Mar 15, 2018 - Debmalya Ray† , Catherine Clark‡ , Hung Q. Pham† , Joshua Borycz† , Russell J. Holmes‡ , Eray S. Aydil‡ , and Laura Gagliar...
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C: Plasmonics, Optical Materials, and Hard Matter

A Computational Study of Structural and Electronic Properties of Lead-Free CsMI3 Perovskites (M = Ge, Sn, Pb, Mg, Ca, Sr, Ba) Debmalya Ray, Catherine Clark, Hung Q. Pham, Joshua Borycz, Russell J. Holmes, Eray S. Aydil, and Laura Gagliardi J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.8b00226 • Publication Date (Web): 15 Mar 2018 Downloaded from http://pubs.acs.org on March 15, 2018

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Prepared for J Phys Chem C.

A Computational Study of Structural and Electronic Properties of Lead-Free CsMI3 Perovskites (M = Ge, Sn, Pb, Mg, Ca, Sr, Ba). Debmalya Raya, Catherine Clarkb, Hung Q. Phama, Joshua Borycza, Russell J. Holmesb, Eray S. Aydilb, Laura Gagliardia* a

Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University

of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455 b

Department of Chemical Engineering and Materials Science, 421 Washington Ave. SE,

Minneapolis, MN 55455 KEYWORDS: perovskites, local density functionals, bandgap, band structures, phase stability

ABSTRACT Electronic structure calculations of five crystallography-imitated structures of CsMI3 perovskites with M = Ge, Sn, Pb, Mg, Ca, Sr, Ba, were performed. The formation energy of different perovskite phases, their relative stability and structural and electronic properties were explored. The sensitivity of the calculations to the choice of the density functional was investigated and the predictions were compared with experimental results. The outcome of this study is that Mg and Ba perovskites are unlikely to form in the cubic, tetragonal or orthorhombic phases because they have positive formation energies. While Ca and Sr perovskites have negative formation energies with respect to the metal iodide precursors, they exhibit wide bandgaps and high hygroscopicity,

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making these unlikely candidates for applications in photovoltaic devices. Our results suggest that the performance of a local density functional with a non-separable gradient approximation is similar to hybrid functionals in terms of bandgap predictions when M in CsMI3 is a p-block element (Pb, Sn, Ge). However, local density functionals with non-separable gradient approximation predictions for the bandgap are similar to other local functionals with a generalized gradient approximation (PBE, PBEsol, PBE-D3) and are worse than those of HSE06 when M is an s-block element (Mg, Ca, Sr, Ba). 1. INTRODUCTION Inorganic and hybrid organic-inorganic halide perovskites have emerged in the last decade as promising materials for efficient, low-cost, thin film solar cells that can be deployed on a largescale.1–16 Devices based on lead halide perovskites have reached power conversion efficiencies of >22%,12 rivaling established solar cell materials including cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and single-crystal Si.17 The archetypal hybrid organic-inorganic halide perovskite, CH3NH3PbI3, has a bandgap near the Shockley-Quessier optimum,18,19 strong absorption in the visible spectrum,2,20–22 long carrier lifetimes,23,24 and high charge carrier mobilities.9,25,26 Consequently, CH3NH3PbI3 can act both as a light absorber and as an efficient charge transporting layer in a solar cell. One of the major concerns, however, is the toxicity of lead. The use of lead is particularly problematic because lead perovskites tend to decompose in ambient conditions, releasing harmful compounds such as PbI2.27–29 In an effort to find novel non-toxic perovskites for photovoltaics, significant experimental and computational work has sought to identify metal cation replacements for lead.26,30–39 Experimentally, the most well-studied alternative to lead is tin (e.g. CH3NH3SnI3). While tin is

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electronically similar to lead and can exist in the +2 oxidation state, tin favors the +4 oxidation state. So far, tin halide solar cells have only achieved a reported maximum efficiency of 9.0%,40 considerably lower than devices based on lead. These low efficiencies are thought to be due to oxidation of Sn(II) to Sn(IV).41,42 No other lead-free perovskites have approached the high efficiencies realized in lead-based solar cells. Computationally, a broad array of potential lead cation replacements have been explored.34,43,44 However, most studies typically examine only one crystal structure (e.g., tetragonal or cubic), without comparing the formation energies between different structures. Since many of these compounds have not been experimentally synthesized, comparison between multiple crystal structures is necessary to help identify the structural properties of those that may be stable and synthesized in the laboratory. Furthermore, computational studies use different types of functionals, but often only one in a single study, making it difficult to compare results from different investigations. Herein, we report the results of a systematic computational study that elucidates the electronic structures of inorganic CsMI3 (M = Pb, Sn, Ge, Mg, Ca, Sr, Ba) perovskites across five crystallography-imitated structures. We compute these results using several Kohn-Sham density functionals, namely generalized gradient approximation (GGA), non-separable gradient approximation (NGA), and hybrid functionals. We also investigated the effect of spin-orbit coupling (SOC) on the bandgaps of all the CsMI3 structures and show the importance of including SOC on the bandgap for different s-block and p-block metals. While it is well known that the predicted values of the bandgap can depend on the functional used, few studies report the formation energy for different crystal structures and their relative stabilities45 and even fewer consider the dependence of formation energy on the choice of the functional. To the best of our

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knowledge, this is the first comprehensive DFT study that compares formation energy and relative stability across several functionals for halide perovskites. We consider the alkaline earth metals Mg, Ca, Sr, Ba as potential replacements for lead in an ABX3 perovskite, and compare the results with those from calculations for Ge, Sn, and Pb. We focus on the structural and electronic properties, the formation energies, and the relative stabilities of the different perovskite phases. We explore how predictions of these properties depend on the choice of the density functional. Finally, we reconcile these predictions with experimental data. 2. COMPUTATIONAL DETAILS The perovskites (see Figure 1a) modeled in this work are CsMI3 (M = Pb, Sn, Ge, Mg, Ca, Sr, Ba).

Cesium was chosen for the A-site due to significant recent interest in all-inorganic

perovskites.46,47 Additionally, modeling perovskites with the spherically symmetric cesium cation is much more computationally affordable than with its similarly-sized organic counterpart CH3NH3+, allowing extensive comparisons between different combinations of functionals and structures.43 We considered five different initial structures as the starting atomic configuration in the geometry optimization. These were constructed using the perovskite platonic model43,48 (the high symmetry point of platonic model are shown Figure 1b) where the CsMI3 crystal structure consists of corner-sharing MI6 octahedra. Following Filip et al.,43 the metal-iodide bond lengths were initially set at 3.1 Å and different values of apical (αa) and equatorial (αe) metal-halidemetal bond angles were used in order to create different orientations of the MI6 octahedra, resulting in five crystallographically-imitated structures: cubic, tetragonal 1, tetragonal 2 (out-ofplane tetragonal), orthorhombic 1, and orthorhombic 2 (see Figure 1c).43,48 The “conventional

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unit cells” in the platonic perovskite model are tetragonal, and are composed of four CsMI3 units. To facilitate the comparison of calculated and experimentally determined lattice parameters, the computationally determined structures were transformed into standard conventional unit cells. With the exception of CsGeI3, the space groups of the computationally determined structures matched the experimental data when such data were available. For CsGeI3, the computationally determined structure was cubic with space group Pm3m, whereas the reported experimental structure is trigonal with space group R3m.49 The Pm3m CsGeI3 structure was further transformed into the R3m space group by using the transformation matrix [(1, 0, -1); (-1, 1, 0); (1, 1, 1)]. All transformations were done using the Material Studio 6.1 software. Periodic density functional theory (DFT) calculations of the CsMI3 (M = Pb, Sn, Ge, Mg, Ca, Sr, Ba) structures were performed using the Vienna Ab Initio Simulation Package (VASP).50–53 Starting with initial guesses of the atomic coordinates in each of the five structures shown in Figure 1c, the crystal structures were determined by minimizing the energy while retaining the symmetry of the initial guess. These structural relaxation calculations were repeated using different functionals, including PBE,54 PBE-D3,55 PBEsol,56 GAM,57 and HSE06.58–61 Among these functionals PBE, PBE-D3, PBEsol are GGA functionals, while GAM is a NGA functional and HSE06 is a hybrid functional. In the GGA approximation, the total energy of the system is expressed in terms of the electron density and its gradient. In NGA functionals, the total exchange and the correlation part are not separated, and instead are treated together. Hybrid functionals like HSE06 account for the non-local exchange interactions by including a percent of Hartree-Fock exchange (25% Hartree-Fock exchange for HSE06). The projected augmented wave (PAW)62,63 potentials were used to describe the interactions between the core and the valence electrons. A plane-wave kinetic energy cutoff of 670 eV was used for all the functionals

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except for HSE06, for which the cutoff was set to 400 eV to reduce the computational time (as HSE06 calculations are computationally intense). The structural relaxation was done by sampling the Brillouin zone over a 6×6×6 k-point grid centered at the Г point. An energy convergence criterion of 10-5 eV was used in the geometry optimization. The atomic positions were relaxed until the forces were less than 0.02 eV/Å. The effect of spin-orbit coupling64 on the CsMI3 bandgaps was investigated using the HSE06 functional with a 4×4×4 k-point mesh. Since we use a tetragonal unit cell with four CsMI3 units for all perovskite phases studied here, we are able to explore their Brillouin zones using the same paths, i.e. Y-Γ and Γ-Z, as defined in Figure 1b. The band structures computed by HSE06 and GAM were plotted along these paths to benchmark the capability of the GAM functional in computing the band dispersions of halide perovskites against HSE06.

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Figure 1. Cesium metal iodide perovskites (CsMI3, M = Ge, Sn, Pb, Mg, Ca, Sr, Ba): (a) Generic CsMI3 crystal structure viewed along the [100] direction; (b) First Brillouin zone (FBZ) of a tetragonal cell and its high symmetry points (Г, X, Y, Z); (c) Five starting structures of perovskite viewed along the [001] direction: cubic, tetragonal 1, tetragonal 2, orthorhombic 1, orthorhombic 2. As discussed in literature,43,48 αa and αe are the initial apical and equatorial metal-halide-metal bond angles used to construct five different phases of perovskite. 3. RESULTS AND DISCUSSION 3.1. Structural Characterization

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It is well known that hybrid DFT functionals such as HSE06 can accurately predict certain experimentally measured structural properties such as lattice parameters.65 In our calculations, we used HSE06 as a benchmark, and found that all other functionals perform similarly in predicting the lattice parameters, with PBEsol and PBE-D3 underestimating them by 1-2%. We compared the HSE06 predictions to experimentally determined lattice parameters, when available, and found that they are within the experimentally reported range for the cubic phase of CsPbI3 and within 1% or less of the experimental values for the cubic and tetragonal phases of CsSnI3 (Table 1). The calculated orthorhombic 1 and orthorhombic 2 lattice parameters are different, due to different tilting of the MI6 octahedra (see Supporting Information Section 1). The experimentally synthesized orthorhombic phase is expected to exhibit dynamic disorder of the MI6 units,66 making head-to-head comparison with calculations difficult. Perhaps for this reason the deviation between some of the experimentally measured and predicted parameters is slightly worse for the orthorhombic phases (1-2% as opposed to 6.2 eV. To support our experimental observation, an HSE06 calculation was performed for the orthorhombic 2 phase of CsSrBr3 yielding a formation energy of -21.8 kcal/mol, similar to that of CsSrI3. The calculated XRD pattern using the orthorhombic 2 phase is similar to the pattern of the XRD peaks obtained by experimental synthesized peaks, however, all the predicted XRD peaks obtained using HSE06 optimized orthorhombic 2 structure are shifted towards left. This is due to the fact that HSE06 optimized orthorhombic 2 structure overestimates the lattice parameter by 0.1 Å when compared to experimental values. Similar disagreements in lattice parameters between theory and experiment are not uncommon and, in fact, are observed in the literature for different perovskites and perovskite like compounds.35,39,109,110 The orthorhombic 2 structure showed a bandgap of 5.7 eV using the HSE06 functional. Comparison of lattice parameters, formation energy and bandgap using different functionals are reported in Supporting Information Section 8.

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+ + CsBr * SrBr2

2:1 CsBr:SrBr2 +

Normalized Intensity (a.u.)

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+

+

1:1 CsBr:SrBr2

1:2 CsBr:SrBr2

*

*

*

*** *

35

40

*

CsSrBr3 orthorhombic 2

CsSrBr3

15

20

25

30

45

50

2θ (°)

Figure 6: X-ray diffraction patterns for different stoichiometries of CsBr and SrBr2 precursors used to synthesize CsSrBr3. All three ratios (blue traces) show the formation of the CsSrBr3 perovskite (black sticks). As expected, the 1:2 ratio also contains excess SrBr2 (red asterisks), and the 2:1 ratio contains excess CsBr (orange crosses). The stability of CsSrBr3 in ambient conditions (Supporting Information Section 6, Figure S2) was evaluated as a function of air exposure time via in situ XRD. A significant change in the diffraction pattern was observed after only 15 minutes of air exposure. Within 60 minutes, the

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XRD pattern was almost completely that of SrBr2·6H2O. This rapid degradation in the presence of moisture, along with its large optical bandgap, indicates this material is unlikely to be useful in PV applications. CONCLUSION We computed formation energies, structural and electronic properties of CsMI3 perovskites, where M = Ge, Sn, Pb, Mg, Ca, Sr, Ba, using several density functionals. We found that Mg and Ba perovskites are unlikely to form in cubic, tetragonal or orthorhombic perovskite phases, which is corroborated by experimental evidence presented here and in the literature. We also found that the formation energy of Sr perovskites is more negative than that of Pb perovskites. While their predicted wide bandgap makes them unlikely candidates as solar absorbers, they may find other applications where wider gaps are desired. However, extreme hygroscopicity of Sr perovskites is a significant challenge. Finally, we showed that the local functional GAM performed similar to the hybrid functional HSE06 for p-block element perovskites, but had less satisfactory performance for s-block perovskites. ASSOCIATED CONTENT Supporting Information. Details of the lattice constants, formation energies, bandgaps, projected band states at Г by different XC functional. AUTHOR INFORMATION Corresponding Author * E-mail: [email protected] (Laura Gagliardi). Author Contribution

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The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript. Notes The authors declare no competing financial interest. ACKNOWLEDGMENT This work was supported primarily by the National Science Foundation through the University of Minnesota MRSEC under Award Number DMR-1420013 and the iSuperseed program. Parts of this work were carried out in the College of Science and Engineering Characterization Facility, University of Minnesota, which has received capital equipment funding from the NSF through the UMN MRSEC program under Award Number DMR-1420013. We would also like to thank Minnesota Supercomputing Institute for computing resources.

REFERENCES (1) (2) (3) (4)

(5) (6) (7) (8)

Manser, J. S.; Christians, A.; Kamat, P. V. Intriguing Optoelectronic Properties of Metal Halide Perovskites. Chem. Rev. 2016, 116, 12956–13008. Green, M. a.; Ho-Baillie, A.; Snaith, H. J. The Emergence of Perovskite Solar Cells. Nat. Photonics 2014, 8, 506–514. Boix, P. P.; Nonomura, K.; Mathews, N.; Mhaisalkar, S. G. Current Progress and Future Perspectives for Organic/inorganic Perovskite Solar Cells. Mater. Today 2014, 17, 16–23. He, M.; Zheng, D.; Wang, M.; Lin, C.; Lin, Z. High Efficiency Perovskite Solar Cells: From Complex Nanostructure to Planar Heterojunction. J. Mater. Chem. A 2014, 2, 5994– 6003. Zhang, G.; Liu, G.; Wang, L.; Irvine, J. T. S. Inorganic Perovskite Photocatalysts for Solar Energy Utilization. Chem. Soc. Rev. 2016, 45, 5951–5984. Manser, J. S.; Saidaminov, M. I.; Christians, J. A.; Bakr, O. M.; Kamat, P. V. Making and Breaking of Lead Halide Perovskites. Acc. Chem. Res. 2016, 49, 330–338. Boix, P. P.; Agarwala, S.; Koh, T. M.; Mathews, N.; Mhaisalkar, S. G. Perovskite Solar Cells: Beyond Methylammonium Lead Iodide. J. Phys. Chem. Lett. 2015, 6, 898–907. Fabini, D. H.; Labram, J. G.; Lehner, A. J.; Bechtel, J. S.; Evans, H. A.; Ven, A. Van Der;

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(9) (10) (11)

(12)

(13)

(14)

(15)

(16)

(17) (18)

(19)

(20)

(21)

(22)

(23)

Page 28 of 35

Wudl, F.; Chabinyc, M. L.; Seshadri, R. Main-Group Halide Semiconductors Derived from Perovskite: Distinguishing Chemical, Structural, and Electronic Aspects. Inorg. Chem. 2017, 56, 11–25. Grätzel, M. The Light and Shade of Perovskite Solar Cells. Nat. Mater. 2014, 13, 838– 842. Zhang, W.; Eperon, G. E.; Snaith, H. J. Metal Halide Perovskites for Energy Applications. Nat. Energy 2016, 1, 16048. Jeon, N. J.; Noh, J. H.; Yang, W. S.; Kim, Y. C.; Ryu, S.; Seo, J.; Seok, S. Il. Compositional Engineering of Perovskite Materials for High-Performance Solar Cells. Nature 2015, 517, 476–480. Yang, W. S.; Park, B.-W.; Jung, E. H.; Jeon, N. J.; Kim, Y. C.; Lee, D. U.; Shin, S. S.; Seo, J.; Kim, E. K.; Noh, J. H.; et al. Iodide Management in Formamidinium-LeadHalide–based Perovskite Layers for Efficient Solar Cells. Science 2017, 356, 1376–1379. Wang, Z.; Lin, Q.; Chmiel, F. P.; Sakai, N.; Herz, L. M.; Snaith, H. J. Efficient AmbientAir-Stable Solar Cells with 2D–3D Heterostructured Butylammonium-CaesiumFormamidinium Lead Halide Perovskites. Nat. Energy 2017, 2, 17135. Saliba, M.; Matsui, T.; Seo, J.-Y.; Domanski, K.; Correa-Baena, J.-P.; Nazeeruddin, M. K.; Zakeeruddin, S. M.; Tress, W.; Abate, A.; Hagfeldt, A.; et al. Cesium-Containing Triple Cation Perovskite Solar Cells: Improved Stability, Reproducibility and High Efficiency. Energy Environ. Sci. 2016, 9, 1989–1997. Eperon, A. G. E.; Leijtens, T.; Bush, K. A.; Green, T.; Tse-, J.; Wang, W.; Mcmeekin, D. P.; Volonakis, G.; Milot, R. L.; Slotcavage, D. J.; et al. Perovskite-Perovskite Tandem Photovoltaics with Ideal Bandgaps. Science 2016, 354, 861–865. Correa-Baena, J.-P.; Saliba, M.; Buonassisi, T.; Grätzel, M.; Abate, A.; Tress, W.; Hagfeldt, A. Promises and Challenges of Perovskite Solar Cells. Science 2017, 358, 739– 744. National Renewable Energy Laboratory. Research Cell Record Efficiency Chart; 2017. Filip, M. R.; Giustino, F. GW Quasiparticle Band Gap of the Hybrid Organic-Inorganic Perovskite CH3NH3PbI3: Effect of Spin-Orbit Interaction, Semicore Electrons, and SelfConsistency. Phys. Rev. B 2014, 90, 245144. Baikie, T.; Fang, Y.; Kadro, J. M.; Schreyer, M.; Wei, F.; Mhaisalkar, S. G.; Gratzel, M.; White, T. J. Synthesis and Crystal Chemistry of the Hybrid Perovskite (CH3NH3)PbI3 for Solid-State Sensitised Solar Cell Applications. J. Mater. Chem. A 2013, 1, 5628–5641. Wolf, S. de; Holovsky, J.; Moon, S.-J.; Löper, P.; Niesen, B.; Ledinsky, M.; Haug, F.; Yum, J.; Ballif, C. Organometallic Halide Perovskites: Sharp Optical Absorption Edge and Its Relation to Photovoltaic Performance. J. Phys. Chem. Lett. 2014, 5, 1035–1039. Tvingstedt, K.; Malinkiewicz, O.; Baumann, A.; Deibel, C.; Snaith, H. J.; Dyakonov, V.; Bolink, H. J. Radiative Efficiency of Lead Iodide Based Perovskite Solar Cells. Sci. Rep. 2014, 4, 6071. Shi, D.; Adinolfi, V.; Comin, R.; Yuan, M.; Alarousu, E.; Buin, A.; Chen, Y.; Hoogland, S.; Rothenberger, A.; Katsiev, K.; et al. Low Trap-State Density and Long Carrier Diffusion in Organolead Trihalide Perovskite Single Crystals. Sci. Rep. 2015, 347, 519– 522. Stranks, S. D.; Eperon, G. E.; Grancini, G.; Menelaou, C.; Alcocer, M. J. P.; Leijtens, T.; Herz, L. M.; Petrozza, A.; Snaith, H. J. Electron-Hole Diffusion Lengths Exceeding 1 Micrometer in an Organometal Trihalide Perovskite Absorber. Science 2013, 342, 341–

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(25)

(26)

(27)

(28)

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(31) (32)

(33)

(34)

(35) (36) (37)

(38)

(39)

344. Xing, G.; Mathews, N.; Lim, S. S.; Lam, Y. M.; Mhaisalkar, S.; Sum, T. C. Long-Range Balanced Electron- and Hole-Transport Lengths in Organic-Inorganic CH3NH3PbI3. Science 2013, 342, 344–347. Wehrenfennig, C.; Eperon, G. E.; Johnston, M. B.; Snaith, H. J.; Herz, L. M. High Charge Carrier Mobilities and Lifetimes in Organolead Trihalide Perovskites. Adv. Mater. 2014, 26, 1584–1589. Stoumpos, C. C.; Malliakas, C. D.; Kanatzidis, M. G. Semiconducting Tin and Lead Iodide Perovskites with Organic Cations: Phase Transitions, High Mobilities, and nearInfrared Photoluminescent Properties. Inorganic Chemistry 2013, 52, 9019–9038. Babayigit, A.; Duy Thanh, D.; Ethirajan, A.; Manca, J.; Muller, M.; Boyen, H.-G.; Conings, B. Assessing the Toxicity of Pb- and Sn-Based Perovskite Solar Cells in Model Organism Danio Rerio. Sci. Rep. 2016, 6, 18721. Eperon, G. E.; Habisreutinger, S. N.; Leijtens, T.; Bruijnaers, B. J.; Van Franeker, J. J.; Dequilettes, D. W.; Pathak, S.; Sutton, R. J.; Grancini, G.; Ginger, D. S.; et al. The Importance of Moisture in Hybrid Lead Halide Perovskite Thin Film Fabrication. ACS Nano 2015, 9, 9380–9393. Babayigit, A.; Ethirajan, A.; Muller, M.; Conings, B. Toxicity of Organometal Halide Perovskite Solar Cells. Nat. Mater. 2016, 15, 247–251. Guo, Y.; Wang, Q.; Saidi, W. A. Structural Stabilities and Electronic Properties of HighAngle Grain Boundaries in Perovskite Cesium Lead Halides. J. Phys. Chem. C 2017, 121, 1715–1722. Trots, D. M.; Myagkota, S. V. High-Temperature Structural Evolution of Caesium and Rubidium Triiodoplumbates. J. Phys. Chem. Solids 2008, 69, 2520–2526. Ahmad, M.; Rehman, G.; Ali, L.; Shafiq, M.; Iqbal, R.; Ahmad, R.; Khan, T.; JalaliAsadabadi, S.; Maqbool, M.; Ahmad, I. Structural, Electronic and Optical Properties of CsPbX3 (X=Cl, Br, I) for Energy Storage and Hybrid Solar Cell Applications. J. Alloys Compd. 2017, 705, 828–839. Yamada, K.; Funabiki, S.; Horimoto, H.; Matsui, T.; Okuda, T.; Ichiba, S. Structural Phase Transitions of the Polymorphs of CsSnI3 by Means of Rietveld Analysis of the XRay Diffraction. Chem. Lett. 1991, pp 801–804. Huang, L. Y.; Lambrecht, W. R. L. Electronic Band Structure, Phonons, and Exciton Binding Energies of Halide Perovskites CsSnCl3, CsSnBr3, and CsSnI3. Phys. Rev. B 2013, 88, 165203. Huang, L. Y.; Lambrecht, W. R. L. Electronic Band Structure Trends of Perovskite Halides: Beyond Pb and Sn to Ge and Si. Phys. Rev. B 2016, 93, 195211. Borriello, I.; Cantele, G.; Ninno, D. Ab Initio Investigation of Hybrid Organic-Inorganic Perovskites Based on Tin Halides. Phys. Rev. B 2008, 77, 235214. Tang, L.-C.; Chang, C.-S.; Tang, L.-C.; Huang, J. Y. Electronic Structure and Optical Properties of Rhombohedral CsGeI3 Crystal. J. Phys. Condens. Matter 2017, 12, 9129– 9143. Krishnamoorthy, T.; Ding, H.; Yan, C.; Leong, W. L.; Baikie, T.; Zhang, Z.; Sherburne, M.; Li, S.; Asta, M.; Mathews, N.; et al. Lead-Free Germanium Iodide Perovskite Materials for Photovoltaic Applications. J. Mater. Chem. A 2015, 3, 23829–23832. Shwetha, G.; Kanchana, V. Optical Isotropy in Structurally Anisotropic Halide Scintillators : Ab Initio Study. Phys. Rev. B 2012, 86, 115209.

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The Journal of Physical Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(40)

(41)

(42)

(43) (44)

(45)

(46)

(47)

(48) (49)

(50)

(51) (52) (53) (54) (55)

(56)

Page 30 of 35

Shao, S.; Liu, J.; Portale, G.; Fang, H.; Blake, G. R.; ten Brink, G. H.; Koster, L. J. A.; Loi, M. A. Highly Reproducible Sn‐Based Hybrid Perovskite Solar Cells with 9% Efficiency. Advanced Energy Materials 2017, 1702019. Parrott, E. S.; Milot, R. L.; Stergiopoulos, T.; Snaith, H. J.; Johnston, M. B.; Herz, L. M. Effect of Structural Phase Transition on Charge-Carrier Lifetimes and Defects in CH3NH3SnI3 Perovskite. J. Phys. Chem. Lett. 2016, 7, 1321–1326. Hao, F.; Stoumpos, C. C.; Guo, P.; Zhou, N.; Marks, T. J.; Chang, R. P. H.; Kanatzidis, M. G. Solvent-Mediated Crystallization of CH3NH3SnI3 Films for Heterojunction Depleted Perovskite Solar Cells. J. Am. Chem. Soc. 2015, 137, 11445–11452. Filip, M. R.; Giustino, F. Computational Screening of Homovalent Lead Substitution in Organic − Inorganic Halide Perovskites. J. Phys. Chem. C 2016, 120, 166–173. Ming, W.; Shi, H.; Du, M. H. Large Dielectric Constant, High Acceptor Density, and Deep Electron Traps in Perovskite Solar Cell Material CsGeI3. J. Mater. Chem. A 2016, 4, 1–7. Jacobsson, T. J.; Pazoki, M.; Hagfeldt, A.; Edvinsson, T. Goldschmidt Rules and Strontium Replacement in Lead Halogen Perovskite Solar Cells: Theory and Preliminary Experiments on CH3NH3SrI3. J. Phys. Chem. C 2015, 119, 25673–25683. Hutter, E. M.; Sutton, R. J.; Chandrashekar, S.; Abdi-Jalebi, M.; Stranks, S. D.; Snaith, H. J.; Savenije, T. J. Vapour-Deposited Cesium Lead Iodide Perovskites: Microsecond Charge Carrier Lifetimes and Enhanced Photovoltaic Performance. ACS Energy Lett. 2017, 2, 1901–1908. Zhang, J.; Wang, Q.; Zhang, X.; Jiang, J.; Gao, Z.; Jin, Z.; Liu, S. (Frank). HighPerformance Transparent Ultraviolet Photodetectors Based on Inorganic Perovskite CsPbCl3 Nanocrystals. RSC Adv. 2017, 7, 36722–36727. Filip, M. R.; Eperon, G. E.; Snaith, H. J.; Giustino, F. Steric Engineering of Metal-Halide Perovskites with Tunable Optical Band Gaps. Nat. Commun. 2014, 5, 1–9. Stoumpos, C. C.; Frazer, L.; Clark, D. J.; Kim, Y. S.; Rhim, S. H.; Freeman, A. J.; Ketterson, J. B.; Jang, J. I.; Kanatzidis, M. G. Hybrid Germanium Iodide Perovskite Semiconductors: Active Lone Pairs, Structural Distortions, Direct and Indirect Energy Gaps, and Strong Nonlinear Optical Properties. J. Am. Chem. Soc. 2015, 137, 6804–6819. Kresse, G.; Hafner, J. Ab Initio Molecular-Dynamics Simulation of the Liquid-Metal– amorphous-Semiconductor Transition in Germanium. Phys. Rev. B 1994, 49, 14251– 14269. Kresse, G.; Furthmüller, J. Efficient Iterative Schemes for Ab Initio Total-Energy Calculations Using a Plane-Wave Basis Set. Phys. Rev. B 1996, 54, 11169–11186. Kresse, G.; Hafner, J. Ab Initio Molecular Dynamics for Liquid Metals. Phys. Rev. B 1993, 47, 558–561. Kresse, G.; Furthmüller, J. Efficiency of Ab-Initio Total Energy Calculations for Metals and Semiconductors Using a Plane-Wave Basis Set. Comput. Mater. Sci. 1996, 6, 15–50. Perdew, J. P.; Wang, Y. Accurate and Simple Analytic Representation of the Electron-Gas Correlation Energy. Phys. Rev. B 1992, 45, 13244–13249. Grimme, S.; Antony, J.; Ehrlich, S.; Krieg, H. A Consistent and Accurate Ab Initio Parametrization of Density Functional Dispersion Correction (DFT-D) for the 94 Elements H-Pu. J. Chem. Phys. 2010, 132, 154104. Perdew, J.; Ruzsinszky, A.; Csonka, G.; Vydrov, O.; Scuseria, G.; Constantin, L.; Zhou, X.; Burke, K. Restoring the Density-Gradient Expansion for Exchange in Solids and

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The Journal of Physical Chemistry

(57)

(58)

(59) (60)

(61)

(62) (63) (64)

(65)

(66) (67)

(68)

(69) (70)

(71) (72)

(73) (74)

Surfaces John. Phys. Rev. Lett. 2008, 100, 136406. Yu, H. S.; Zhang, W.; Verma, P.; He, X.; Truhlar, D. G. Nonseparable Exchange– Correlation Functional for Molecules, Including Homogeneous Catalysis Involving Transition Metals. Phys. Chem. Chem. Phys. 2015, 17, 12146–12160. Paier, J.; Marsman, M.; Hummer, K.; Kresse, G.; Gerber, I. C.; Angyán, J. G. Erratum: “Screened Hybrid Density Functionals Applied to Solids” [J. Chem. Phys. 124, 154709(2006)]. J. Chem. Phys. 2006, 125, 249901. Heyd, J.; Scuseria, G. E. Assessment and Validation of a Screened Coulomb Hybrid Density Functional. J. Chem. Phys. 2004, 120, 7274–7280. Heyd, J.; Scuseria, G. E.; Ernzerhof, M. Erratum: Hybrid Functionals Based on a Screened Coulomb Potential (Journal of Chemical Physics (2003) 118 (8207)). J. Chem. Phys. 2006, 124, 219906. Heyd, J.; Peralta, J. E.; Scuseria, G. E.; Martin, R. L. Energy Band Gaps and Lattice Parameters Evaluated with the Heyd-Scuseria-Ernzerhof Screened Hybrid Functional. J. Chem. Phys. 2005, 123, 174101. Kresse, G. From Ultrasoft Pseudopotentials to the Projector Augmented-Wave Method. Physical Review B 1999, 59, 1758–1775. Blöchl, P. E. Projector Augmented-Wave Method. Phys. Rev. B 1994, 50, 17953–17979. Steiner, S.; Khmelevskyi, S.; Marsmann, M.; Kresse, G. Calculation of the Magnetic Anisotropy with Projected-Augmented-Wave Methodology and the Case Study of Disordered Fe 1 − X Co X Alloys. Phys. Rev. B 2016, 93, 224425. Lai, M.; Kong, Q.; Bischak, C. G.; Yu, Y.; Dou, L.; Eaton, S. W.; Ginsberg, N. S.; Yang, P. Structural, Optical, and Electrical Properties of Phase-Controlled Cesium Lead Iodide Nanowires. Nano Res. 2017, 10, 1107–1114. Whalley, L. D.; Frost, J. M.; Jung, Y.-K.; Walsh, A. Perspective: Theory and Simulation of Hybrid Halide Perovskites. J. Chem. Phys. 2017, 146, 220901. Eperon, G. E.; Paternò, G. M.; Sutton, R. J.; Zampetti, A.; Haghighirad, A. A.; Cacialli, F.; Snaith, H. J. Inorganic Caesium Lead Iodide Perovskite Solar Cells. J. Mater. Chem. A 2015, 3, 19688–19695. Schilling, G.; Meyer, G. Ternare Bromide Und Iodide Zweiwertiger Lanthanide Und Ihre Erdalkali-Analoga Vom Typ AMX3 Und AM2X5. Z. Anorg. All. Chem. 1996, 622, 759– 765. Garza, A. J.; Scuseria, G. E. Predicting Band Gaps with Hybrid Density Functionals. J. Phys. Chem. Lett. 2016, 7, 4165–4170. Chung, I.; Song, J.-H.; Im, J.; Androulakis, J.; Malliakas, C. D.; Li, H.; Freeman, A. J.; Kenney, J. T.; Kanatzidis, M. G. CsSnI3 : Semiconductor or Metal? High Electrical Conductivity and Strong Near-Infrared Photoluminescence from a Single Material. High Hole Mobility and Phase-Transitions. J. Am. Chem. Soc. 2012, 134, 8579–8587. Shi, H.; Du, M. Shallow Halogen Vacancies in Halide Optoelectronic Materials. Phys. Rev. B 2014, 90, 174103. Even, J.; Pedesseau, L.; Jancu, J.; Katan, C. Importance of Spin − Orbit Coupling in Hybrid Organic/Inorganic Perovskites for Photovoltaic Applications. J. Phys. Chem. Lett. 2013, 4, 2999–3005. Hendon, C. H.; Yang, R. X.; Burton, L. A.; Walsh, A. Assessment of Polyanion (BF4 − and PF6 − ) Substitutions in Hybrid Halide Perovskites. J. Mater. Chem. A 2015, 3, 9067–9070. Afsari, M.; Boochani, A.; Hantezadeh, M.; Elahi, S. M. Topological Nature in Cubic

ACS Paragon Plus Environment

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The Journal of Physical Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(75)

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(78)

(79) (80) (81)

(82)

(83)

(84)

(85)

(86)

(87)

(88)

(89)

Page 32 of 35

Phase of Perovskite CsPbI3: By DFT. Solid State Commun. 2017, 259, 10–15. Li, Y.; Zhang, C.; Zhang, X.; Huang, D.; Shen, Q.; Cheng, Y.; Huang, W. Intrinsic Point Defects in Inorganic Perovskite CsPbI3 from First-Principles Prediction. Appl. Phys. Lett. 2017, 111, 162106. Grote, C.; Berger, R. F. Strain Tuning of Tin-Halide and Lead-Halide Perovskites: A First-Principles Atomic and Electronic Structure Study. J. Phys. Chem. C 2015, 119, 22832–22837. Krishnamoorthy, T.; Ding, H.; Yan, C.; Leong, W. L.; Baikie, T.; Zhang, Z.; Sherburne, M.; Li, S.; Asta, M.; Mathews, N.; et al. Lead-Free Germanium Iodide Perovskite Materials for Photovoltaic Applications. J. Mater. Chem. A 2015, 3, 23829–23832. Debbichi, L.; Lee, S.; Cho, H.; Rappe, A. M.; Hong, K.-H.; Jang, M. S.; Kim, H. Mixed Valence Perovskite Cs2 Au2 I6 : A Potential Material for Thin-Film Pb-Free Photovoltaic Cells with Ultrahigh Efficiency. Adv. Mater. 2018, 1707001, 1707001. Sun, P.-P.; Li, Q.-S.; Yang, L.-N.; Li, Z.-S. Theoretical Insights into a Potential Lead-Free Hybrid Perovskite: Substituting Pb2+ with Ge 2+. Nanoscale 2016, 8, 1503–1512. Poglitsch, A.; Weber, D. Dynamic Disorder in Methylammoniumtrihalogenoplumbates (II) Observed by Millimeter-Wave Spectroscopy. J. Chem. Phys. 1987, 87, 6373. Gokhale, S. S.; Stand, L.; Lindsey, A.; Koschan, M.; Zhuravleva, M.; Melcher, C. L. Improvement in the Optical Quality and Energy Resolution of CsSrBr3 : Eu Scintillator Crystals. J. Cryst. Growth 2016, 445, 1–8. Peedikakkandy, L.; Bhargava, P. Composition Dependent Optical, Structural and Photoluminescence Characteristics of Cesium Tin Halide Perovskites. RSC Adv. 2016, 6, 19857–19860. Wu, B.; Zhou, Y.; Xing, G.; Xu, Q.; Garces, H. F.; Solanki, A.; Goh, T. W.; Padture, N. P.; Sum, T. C. Long Minority-Carrier Diffusion Length and Low Surface-Recombination Velocity in Inorganic Lead-Free CsSnI3 Perovskite Crystal for Solar Cells. Adv. Funct. Mater. 2017, 27, 1604818. Sabba, D.; Mulmudi, H. K.; Prabhakar, R. R.; Krishnamoorthy, T.; Baikie, T.; Boix, P. P.; Mhaisalkar, S.; Mathews, N. Impact of Anionic Br – Substitution on Open Circuit Voltage in Lead Free Perovskite (CsSnI3-xBrx ) Solar Cells. J. Phys. Chem. C 2015, 119, 1763– 1767. Kumar, M. H.; Dharani, S.; Leong, W. L.; Boix, P. P.; Prabhakar, R. R.; Baikie, T.; Shi, C.; Ding, H.; Ramesh, R.; Asta, M.; et al. Lead-Free Halide Perovskite Solar Cells with High Photocurrents Realized Through Vacancy Modulation. Adv. Mater. 2014, 26, 7122– 7127. Shum, K.; Chen, Z.; Qureshi, J.; Yu, C.; Wang, J. J.; Pfenninger, W.; Vockic, N.; Midgley, J.; Kenney, J. T. Synthesis and Characterization of CsSnI3 Thin Films. Appl. Phys. Lett. 2010, 96, 221903. Sutton, R. J.; Eperon, G. E.; Miranda, L.; Parrott, E. S.; Kamino, B. A.; Patel, J. B.; Hörantner, M. T.; Johnston, M. B.; Haghighirad, A. A.; Moore, D. T.; et al. BandgapTunable Cesium Lead Halide Perovskites with High Thermal Stability for Efficient Solar Cells. Adv. Energy Mater. 2016, 6, 1502458. Swarnkar, A.; Marshall, A. R.; Sanehira, E. M.; Chernomordik, B. D.; Moore, D. T.; Christians, J. A.; Chakrabarti, T.; Luther, J. M. Quantum Dot–induced Phase Stabilization of α-CsPbI3 Perovskite for High-Efficiency Photovoltaics. Science 2016, 354, 92–95. Luo, P.; Xia, W.; Zhou, S.; Sun, L.; Cheng, J.; Xu, C.; Lu, Y. Solvent Engineering for

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The Journal of Physical Chemistry

(90)

(91)

(92) (93) (94) (95)

(96)

(97) (98) (99) (100)

(101)

(102)

(103)

(104)

(105)

Ambient-Air-Processed, Phase-Stable CsPbI3 in Perovskite Solar Cells. J. Phys. Chem. Lett. 2016, 7, 3603–3608. Protesescu, L.; Yakunin, S.; Bodnarchuk, M. I.; Krieg, F.; Caputo, R.; Hendon, C. H.; Yang, R. X.; Walsh, A.; Kovalenko, M. V. Nanocrystals of Cesium Lead Halide Perovskites (CsPbX3 , X = Cl, Br, and I): Novel Optoelectronic Materials Showing Bright Emission with Wide Color Gamut. Nano Lett. 2015, 15, 3692–3696. Ramasamy, P.; Lim, D.-H.; Kim, B.; Lee, S.-H.; Lee, M.-S.; Lee, J.-S. All-Inorganic Cesium Lead Halide Perovskite Nanocrystals for Photodetector Applications. Chem. Commun. 2016, 52, 2067–2070. Wei, H.; Zhuravleva, M.; Yang, K.; Blalock, B.; Melcher, C. L. Effect of Ba Substitution in CsSrI3:Eu2+. J. Cryst. Growth 2013, 384, 27–32. Zhuravleva, M.; Blalock, B.; Yang, K.; Koschan, M.; Melcher, C. L. New Single Crystal Scintillators: CsCaCl3:Eu and CsCaI3:Eu. J. Cryst. Growth 2012, 352, 115–119. Beurer, E.; Grimm, J.; Gerner, P.; Güdel, H. U. New Type of near-Infrared to Visible Photon Upconversion in Tm2+-Doped CsCal3. J. Am. Chem. Soc. 2006, 128, 3110–3111. Tyagi, M.; Zhuravleva, M.; Melcher, C. L. Theoretical and Experimental Characterization of Promising New Scintillators: Eu2+ Doped CsCaCl3 and CsCaI3. J. Appl. Phys. 2013, 113, 203504. Gokhale, S. S.; Loyd, M.; Stand, L.; Lindsey, A.; Swider, S.; Zhuravleva, M.; Melcher, C. L. Investigation of the Unique Degradation Phenomenon Observed in CsSrBr3: Eu 5% Scintillator Crystals. J. Cryst. Growth 2016, 452, 89–94. Yang, K.; Zhuravleva, M.; Melcher, C. L. Crystal Growth and Characterization of CsSr1xEuxI3 High Light Yield Scintillators. Phys. Status Solidi 2011, 5, 43–45. Suta, M.; Wickleder, C. Photoluminescence of CsMI3 :Eu2+ (M = Mg, Ca, and Sr) – a Spectroscopic Probe on Structural Distortions. J. Mater. Chem. C 2015, 3, 5233–5245. Li, C.; Lu, X.; Ding, W.; Feng, L.; Gao, Y.; Guo, Z. Formability of ABX3 (X = F, Cl, Br, I) Halide Perovskites. Acta Crystallogr. B 2008, B64, 702–707. Mcpherson, G. L.; Mcpherson, A. M.; Atwood, J. L. Structures OF CsMgBr3, CsCdBr3, and CsMgI3-- Diamagnetic Linear Chain Lattices. J. Phys. Chem. Solids 1980, 41, 495– 499. Kumar, A.; Balasubramaniam, K. R.; Kangsabanik, J.; Vikram; Alam, A. Crystal Structure, Stability and Optoelectronic Properties of the Organic-Inorganic Wide Bandgap Perovskite CH3NH3BaI3: Candidate for Transparent Conductor Applications. Phys. Rev. B 2016, 94, 180105. Shirwadkar, U.; Loef, E. V. D. Van; Hawrami, R.; Mukhopadhyay, S.; Glodo, J.; Shah, K. S. New Promising Scintillators for Gamma-Ray Spectroscopy: Cs(Ba,Sr)(Br,I)3. In 2011 IEEE Nuclear Science Symposium Conference Record; 2011; pp 1583–1585. Wojciechowski, K.; Saliba, M.; Leijtens, T.; Abate, A.; Snaith, H. J. Sub-150 °C Processed Meso-Superstructured Perovskite Solar Cells with Enhanced Efficiency. Energy Environ. Sci. 2014, 7, 1142–1147. Zhang, W.; Saliba, M.; Moore, D. T.; Pathak, S. K.; Horantner, M. T.; Stergiopoulos, T.; Stranks, S. D.; Eperon, G. E.; Alexander-Webber, J. A.; Abate, A.; et al. Ultrasmooth Organic-Inorganic Perovskite Thin-Film Formation and Crystallization for Efficient Planar Heterojunction Solar Cells. Nat. Commun. 2015, 6, 6142. Burschka, J.; Pellet, N.; Moon, S.-J.; Humphry-Baker, R.; Gao, P.; Nazeeruddin, M. K.; Grätzel, M. Sequential Deposition as a Route to High-Performance Perovskite-Sensitized

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Page 34 of 35

Solar Cells. Nature 2013, 499, 316–319. Chiang, Y.-H.; Cheng, H.-M.; Li, M.-H.; Guo, T.-F.; Chen, P. Low-Pressure VaporAssisted Solution Process for Thiocyanate-Based Pseudohalide Perovskite Solar Cells. ChemSusChem 2016, 9, 2620–2627. Chen, Q.; Zhou, H.; Hong, Z.; Luo, S.; Duan, H.-S.; Wang, H.-H.; Liu, Y.; Li, G.; Yang, Y. Planar Heterojunction Perovskite Solar Cells via Vapor-Assisted Solution Process. J. Am. Chem. Soc. 2014, 136, 622–625. Rowe, E.; Tupitsyn, E.; Wiggins, B.; Bhattacharya, P.; Matei, L.; Groza, M.; Buliga, V.; Burger, A.; Beck, P.; Cherepy, N. J.; et al. Double Salts Iodide Scintillators: Cesium Barium Iodide, Cesium Calcium Iodide, and Barium Bromine Iodide. Cryst.Res. Technol. 2013, 48, 227–235. Hong, K.-H.; Kim, J.; Debbichi, L.; Kim, H.; Im, S. H. Band Gap Engineering of Cs3Bi2I9 Perovskites with Trivalent Atoms Using a Dual Metal Cation. J. Phys. Chem. C 2017, 121, 969–974. Fang, C. M.; Biswas, K. Quaternary Iodides A(BaSr)I5:Eu2+(A = K, Cs) as Scintillators for Radiation Detection. J. Phys. Chem. C 2016, 120, 1225–1236.

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CsMI3 Perovskites (M = Ge, Sn, Pb, Mg, Ca, Sr, Ba) studied with different density functionals 341x254mm (96 x 96 DPI)

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