Chiral halide perovskite crystals for optoelectronic applications

Chiral halide perovskites are of profound importance in research frontiers. The combination of excellent components of perovskites and unique features of chirality has provided thorough insights into this perovskite optoelectronic area. Here, recent research efforts on chiral halide perovskites are comprehensively summarized, focusing on powder, micro- and nanocrystals, thin films, and bulk single crystals. Chiral halide perovskite single crystals including anisotropic properties and related crystalline devices such as circularly polarized perovskite light-emitting diodes and chiro-spintronic and memory devices will be the challenges and ultimate goals. Chiral halide perovskites have recently emerged as a class of potential optoelectronic materials. In this review, we mainly aim to provide a comprehensive understanding of chiral halide perovskite crystals for optoelectronic applications. An overview of the research background and advancement of chiral halide perovskites is described. Crystal structure, synthesis, and growth methods of chiral halide perovskite single crystals are demonstrated. Moreover, the characteristic properties and optoelectronic applications of chiral halide perovskites are systematically illustrated. Finally, future research opportunities and challenges of chiral halide perovskite single crystals and related devices are provided, concluding with our perspective on the burgeoning optoelectronic field. Chiral halide perovskites have recently emerged as a class of potential optoelectronic materials. In this review, we mainly aim to provide a comprehensive understanding of chiral halide perovskite crystals for optoelectronic applications. An overview of the research background and advancement of chiral halide perovskites is described. Crystal structure, synthesis, and growth methods of chiral halide perovskite single crystals are demonstrated. Moreover, the characteristic properties and optoelectronic applications of chiral halide perovskites are systematically illustrated. Finally, future research opportunities and challenges of chiral halide perovskite single crystals and related devices are provided, concluding with our perspective on the burgeoning optoelectronic field. Chiral materials have attracted significant research interest in various realms from biological science1Lee H. Huttunen M.J. Hsu K.-J. Partanen M. Zhuo G.-Y. Kauranen M. Chu S.-W. Chiral imaging of collagen by second-harmonic generation circular dichroism.Biomed. Opt. Express. 2013; 4: 909-916Crossref PubMed Scopus (51) Google Scholar,2Bentley R. Role of sulfur chirality in the chemical processes of biology.Chem. Soc. Rev. 2005; 34: 609-624Crossref PubMed Scopus (0) Google Scholar to optoelectronic fields.3Dong Y. Zhang Y. Li X. Feng Y. Zhang H. Xu J. 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Bis[(S)- β- phenethylammonium] tribromoplumbate(II).Acta Cryst. E. 2003; 59: m381-m383Crossref PubMed Scopus (20) Google Scholar,18Billing D.G. Lemmerer A. Synthesis and crystal structures of inorganic-organic hybrids incorporating an aromatic amine with a chiral functional group.CrystEngComm. 2006; 8: 686-695Crossref Google Scholar However, the optoelectronic properties based on chiral halide perovskites have not been explored. Recently, chiral perovskite materials have drawn research attention to their diverse properties and their study extended into various optoelectronic fields. In 2017, circular polarization absorption characteristics based on chiral hybrid perovskite thin films were first demonstrated by Ahn et al.19Ahn J. Lee E. Tan J. Yang W. Kim B. Moon J. A new class of chiral semiconductors: chiral-organic-molecule-incorporating organic-inorganic hybrid perovskites.Mater. Horiz. 2017; 4: 851-856Crossref Google Scholar Apart from the chiral perovskite thin films, some reports on chiral perovskite micro-/nanostructures and the effects on the performance of optoelectronic devices were reported.20Georgieva Z.N. Bloom B.P. Ghosh S. Waldeck D.H. Imprinting chirality onto the electronic states of colloidal perovskite nanoplatelets.Adv. Mater. 2018; 30: 1800097Crossref Scopus (22) Google Scholar,21Shi Y. Duan P. Huo S. Li Y. Liu M. Endowing perovskite nanocrystals with circularly polarized luminescence.Adv. Mater. 2018; 30: 1705011Crossref Scopus (69) Google Scholar Two-dimensional (2D) chiral halide perovskite microplates with a high degree of circularly polarized photoluminescence (CPL) and photodetectors were demonstrated.22Ma J. Fang C. Chen C. Jin L. Wang J. Wang S. Tang J. Li D. Chiral 2D perovskites with a high degree of circularly polarized photoluminescence.ACS Nano. 2019; 13: 3659-3665Crossref PubMed Scopus (52) Google Scholar Miyasaka’s group demonstrated that the bulk photovoltaic characteristics based on a pair of Ruddlesen-Popper-type chiral lead iodide perovskite single crystals were altered by the chirality of organic cations.23Huang P.-J. Taniguchi K. Miyasaka H. Bulk photovoltaic effect in a pair of chiral-polar layered perovskite-type lead iodides altered by chirality of organic cations.J. Am. Chem. Soc. 2019; 141: 14520-14523Crossref PubMed Scopus (11) Google Scholar Spin-dependent charge-transport characteristics based on 2D chiral perovskite thin films were systematically studied.24Lu H. Wang J. Xiao C. Pan X. Chen X. Brunecky R. Berry J.J. Zhu K. Beard M.C. Vardeny Z.V. Spin-dependent charge transport through 2D chiral hybrid lead-iodide perovskites.Sci. Adv. 2019; 5: eaay0571Crossref PubMed Scopus (82) Google Scholar Shi’s group reported the switchable photovoltaic ferroelectric characteristics based on one-dimensional (1D) chiral halide perovskites.25Hu Y. Florio F. Chen Z. Phelan W.A. Siegler M.A. Zhou Z. Guo Y. Hawks R. Jiang J. Feng J. et al.A chiral switchable photovoltaic ferroelectric 1D perovskite.Sci. Adv. 2020; 6: eaay4213Crossref PubMed Scopus (5) Google Scholar Recently, hybrid structural chirality transfer in a 2D hybrid perovskite and the impact on Rashba-Dresselhaus spin-orbit coupling have been investigated by Mitzi’s group.26Jana M.K. Song R. Liu H. Khanal D.R. Janke S.M. Zhao R. et al.Organic-to-inorganic structural chirality transfer in a 2D hybrid perovskite and impact on Rashba-Dresselhaus spin-orbit coupling.Nat. Commun. 2020; 11: 4699Crossref PubMed Scopus (32) Google Scholar Until now there have been few reports about bulk chiral halide perovskite single crystals and their optoelectronic applications. In this review, we systematically summarize the recent research progress and discussions of chiral halide perovskites. Moreover, some future directions in the optoelectronic field are provided. This will not only be helpful in understanding the fundamental properties of chiral perovskite materials but will also be significant for crystalline optoelectronic applications of chiral halide perovskites. In dealing with chiral crystal structures, it is vital to distinguish between three different chiroptical active objects: (1) the chiral components of the crystal,27Zhu L. Huang Y. Lin Y. Huang X. Liu H. Mitzi D.B. Du K. Stereo-chemically active lead chloride enantiomers mediated by homochiral organic cation.Polyhedron. 2019; 158: 445-448Crossref Scopus (5) Google Scholar (2) the chiral crystal structure itself,28Kousaka Y. Ohsumi H. Komesu T. Arima T. Takata M. Sakai S. Akita M. Inoue K. Yokobori T. 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Acta. 2003; 86: 905-921Crossref Scopus (282) Google Scholar Generally speaking, two design strategies to obtain chiral perovskite materials include chiral distortion of the perovskite material induced by chiral organic molecules as ligands and helical arrangement-induced chiral perovskite structures. When combined with chiral organic ligands, halide perovskites may be obtained in the form of chiral structures. This chirality transfer can be mediated through the formation of chemical bonds in the chiral perovskite systems shown in Scheme 1A. Most chiral perovskites can be achieved through this strategy. However, helical arrangements in the crystal structures may produce the chiral structures as shown in Scheme 1B. In all the space groups, chiral perovskites included 65 different space groups deduced from the report by Sohncke.32Sohncke L. Entwickelung einer Theorie der Krystallstruktur. Teubner, 1879https://dictionary.iucr.org/Sohncke_groupsGoogle Scholar Forty-three types of non-enantiomorphic space groups may be obtained and adopted by the ligand-induced chirality strategy shown in Scheme 1C. Interestingly 22 types of chiral space groups are enantiomorphic, based on the helical arrangements shown in Scheme 1D. Interestingly, chiroptical properties are also observed for crystal structures based on four kinds of achiral point groups (m, mm2, -4, and -42m).33Gautier R. Klingsporn J.M. Van Duyne R.P. Poeppelmeier K.R. Optical activity from racemates.Nat. Mater. 2016; 15: 591-592Crossref PubMed Scopus (15) Google Scholar These crystal structures all show intriguing optical and electric properties. Chiral halide perovskite materials can be directly obtained by chiral organic ligands, which form different-dimensional halide perovskites. To the best of our knowledge, there have been few reports about chiral organic ligands applied to halide perovskites. Hybrid lead perovskites with only a single enantiomorphic chiral amine as the ligand cation with the chiral space group P212121 (no. 19) were reported.17Billing D.G. Lemmerer A. Bis[(S)- β- phenethylammonium] tribromoplumbate(II).Acta Cryst. E. 2003; 59: m381-m383Crossref PubMed Scopus (20) Google Scholar,18Billing D.G. Lemmerer A. Synthesis and crystal structures of inorganic-organic hybrids incorporating an aromatic amine with a chiral functional group.CrystEngComm. 2006; 8: 686-695Crossref Google Scholar Thereafter, the synthesis and crystal structures of the related chiral halide lead perovskites were introduced, which exhibited essentially the chiral cell parameters with mirror configuration. The representative chiral organic ligands include methylbenzylammonium (MBA), methylphenethylammonium (MPA), cyclohexylethylammonium (CHEA), and +H3N (CH2)2S-S(CH2)2NH3+ (Figure 1). Chiral perovskite systems were then extended to long-chain or polycyclic aromatic amines.34Hajlaoui F. Hadj Sadok I.B. Aeshah H.A. Audebrand N. Roisnel T. Zouari N. Synthesis, crystal structures, second harmonic generation response and temperature phase transitions of two noncentrosymmetric Cu (II)-hybrid halides compounds: [(R)-C7H16N2][CuX4] (X = Cl or Br).J. Mol. Struct. 2019; 1182: 47-53Crossref Scopus (4) Google Scholar,35He T. Li J. Li X. Ren C. Luo Y. Zhao F. Chen R. Lin X. Zhang J. Spectroscopic studies of chiral perovskite nanocrystals.Appl. Phys. Lett. 2017; 111: 151102Crossref Scopus (26) Google Scholar Moreover, the synthesis and crystal structures of lead-free chiral hybrid materials based on cadmium (Cd),36Tang Y.-Y. Ai Y. Liao W. Li P. Wang Z. Xiong R. H/F- substitution-induced homochirality for designing high-Tc molecular perovskite ferroelectrics.Adv. Mater. 2019; 31: 1902163Crossref Scopus (31) Google Scholar cobalt (Co),37Mande H.M. Ghalsasi P.S. Arulsamy N. 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Kajzar F. et al.A switchable NLO organic-inorganic compound based on conformationally chiral disulfide molecules and Bi(III)I5 iodobismuthate networks.Adv. Mater. 2008; 20: 1013-1017Crossref Scopus (188) Google Scholarand tin (Sn)42Black R.S. Billing D.G. The structure and photoluminescence of chiral tin and lead inorganic-organic hybrid perovskites.Acta Cryst. 2008; A64: C455-C456Crossref Google Scholar43Xiao L. An T. Wang L. Xu X. Sun H. Novel properties and applications of chiral inorganic nanostructures.Nano Today. 2020; 30: 100824Crossref Scopus (4) Google Scholar as central elements were demonstrated, but their chiral optoelectronic properties have not yet been investigated. As it is easy to obtain chiral halide perovskites by this ligand-induced chirality strategy, their chiral optoelectronic applications deserve further investigation. Although the chiral ligands produced chiral structures in the halide perovskites, the helical perovskite structures were mainly constructed with the help of the chiral environment or special reaction conditions to effect the nucleation and crystal growth. Ohsumi et al.44Ohsumi H. Tokuda A. Takeshita S. Takata M. Suzuki M. Kawamura N. Kousaka Y. Akimitsu J. Arima T. Three-dimensional near-surface imaging of chirality domains with circularly polarized X-rays.Angew. Chem. Int. Ed. 2013; 52: 8718-8721Crossref PubMed Scopus (9) Google Scholar reported that lead-free inorganic perovskite CsCuCl3 exhibited helical structures with space group P6122 and P6522 due to the Jahn-Teller effect of Cu2+ (Figure 2A). Helical structures of CsCuCl3 are measured on the basis of circular polarized X-rays by using a diamond-phase retarder via Kirkpatrick-Baez mirrors45Takagaki, M., Suzuki, M., Kawamura, N., Mimura, H., Ishikawa, T. (2006). Proceedings of 8th International Conference on X-ray Microscopy. IPAP Conf. Series 7, 267-269.Google Scholar at the sample position (Figure 2B), which is converted by being linearly polarized from a planar undulator insertion device monochromatized to photon energy. The intensity of the 00l (l = 14) reflection was measured with circularly polarized beams to obtain chirality-domain images, because the flipping ratio (R) value is directly related to volume fractions about F(P6122) and F(P6522). For the 00l reflection, R is written as given byR=−2sinθ1+sin2θ[∅(P6122)−∅(P6522)].(Equation 1) Flipping ratio variation on a cleaved (001) surface of CsCuCl3 was measured by scanning the sample crystal in 10-μm steps over 270 × 160 mm2 with X-ray energy of 8.986 keV (Figure 2C), whereby R (−0.83 or +0.83) in P6122 or P6522 single crystal for the 00l (l = 14) reflection was obtained.44Ohsumi H. Tokuda A. Takeshita S. Takata M. Suzuki M. Kawamura N. Kousaka Y. Akimitsu J. Arima T. Three-dimensional near-surface imaging of chirality domains with circularly polarized X-rays.Angew. Chem. Int. Ed. 2013; 52: 8718-8721Crossref PubMed Scopus (9) Google Scholar The three-dimensional (3D) chirality-domain distribution on the CsCuCl3 (001) surface exhibited the morphological features with different chirality-domain distribution (P6122 and P6522) (Figure 2D). Chiroptical activity can only be exhibited for chiral materials, and these descriptions are not correct.46Claborn K. Isborn C. Kaminsky W. Kahr B. Optical rotation of achiral compounds.Angew. Chem. Int. Ed. 2008; 47: 5706-5717Crossref PubMed Scopus (66) Google Scholar, 47O’Loane J.K. Optical activity in small molecules, nonenantiomorphous crystals and nematic liquid crystals.Chem. Rev. 1980; 80: 41-61Crossref Scopus (63) Google Scholar, 48Hobden M.V. 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Soc. 2019; 141: 15755-15760Crossref PubMed Scopus (19) Google Scholar Single-crystal X-ray diffraction (SXRD) analysis demonstrated that (KC)2MnX4 (KC = [K(dibenzo-18-crown-6)]+, X = Cl, Br) belong to the achiral space group of Cc (point group m) (Figure 3). The Mn2+ cation was located at the central position and surrounded by four X− ions to form a tetrahedral [MnX4]2− unit, where two KC were filled with the gap of [MnX4]2− unit by K+-π interactions in an asymmetric unit to produce a right-handed helix and a left-handed helix with the slide and mirror symmetry operation shown in Figure 3A. The layer can be formed by the parallel arrangement of these helices, also based on these interactions between helices (Figure 3B). To the best of our knowledge, there is only one report on achiral halide perovskites showing excellent optical activity. This design strategy should provide guidance for searching the novel chiroptical active materials applied to the optoelectronic field. Chiral perovskite materials can be directly achieved by introducing the known chiral organic ligands and helical structure. More importantly, the material design of chiral halide perovskites can be predicted by theoretical calculations. For traditional achiral perovskite crystals, theoretical calculations based on first principles can provide an insightful understanding and prediction of their optoelectronic properties.50Xiao Z. Yan Y. Progress in theoretical study of metal halide perovskite solar cell materials.Adv. Energy. Mater. 2017; 7: 1701136Crossref Scopus (170) Google Scholar, 51Lin Y.-P. Hu S. Xia B. Fan K.-Q. Gong L.-K. Kong J.-T. Huang X.-Y. Xiao Z. Du K.-Z. Material design and optoelectronic properties of three-dimensional quadruple perovskite halides.J. Phys. Chem. Lett. 2019; 10: 5219-5225Crossref PubMed Scopus (27) Google Scholar, 52Xiao Z. Zhou Y. Hosono H. Kamiya T. Padture N.P. Bandgap optimization of perovskite semiconductors for photovoltaic applications.Chem. Eur. J. 2017; 24: 2305-2316Crossref Scopus (53) Google Scholar For chiral perovskite crystals, theoretical calculations may also play an important role in predicting chiral optoelectronic properties and applications. There have been few reports about theoretical calculations of chiral halide perovskites. Recently, Long et al.53Long G. Zhou Y. Zhang M. Sabatini R. Rasmita A. Huang L. Lakhwani G. Gao W. Theoretical prediction of chiral 3D hybrid organic-inorganic perovskites.Adv. Mater. 2019; 31: 1807628Crossref Scopus (18) Google Scholar reported that 3D hybrid halide perovskites implanting chirality via the chiral methylammonium cation were investigated. The smallest units of (R)- and (S)-deuterotritomethylammonium(CHDTNH3+), and (R)- and (S)-chlorofluoromethylammonium (CHFClNH3+) are shown in Figure 4A. Moreover, in Figures 4B and 4C, the structures of chiral (R)- and (S)-CHFClNH3PbI3 are forecast to be the simplest P2 chiral space group, while (R, S)-CHFClNH3PbI3 was built into the P-1 centrosymmetric space group. Meanwhile, the calculated direct band gap of (R)-, (S)-, and (R, S)-CHFClNH3PbI3 based on the HSE06 functional is 1.51, 1.51, and 1.24 eV, respectively (Figure 4D). By theoretical calculations combined with the impressive optical, electrical, and spintronic properties, chiral perovskites may attract great interest in the field of optoelectronics. As discussed above, chirality is implanted into halide perovskites by different structural design schemes. Chiral perovskite single crystals exhibit stronger chirality behaviors than powders and thin films due to their periodic arrangement. Thus, future studies will focus on obtaining bulk high-quality single crystals. Many synthetic methods have been developed to obtain halide perovskite single crystals. Bulk perovskite single crystals are synthesized and grown by using an HX/H3PO2 (X = Cl, Br, I) solution to dissolve the lead or tin(II) oxide compounds and organic amines by controlling the solution temperature.54Dang Y. Zhou Y. Liu X. Ju D. Xia S. Xia H. Tao X. Formation of hybrid perovskite tin iodide single crystals by top seeded solution growth.Angew. Chem. Int. Ed. 2016; 55: 3447-3450Crossref PubMed Scopus (0) Google Scholar, 55Dang Y. Zhong C. Zhang G. Ju D. Wang L. Xia S. Xia H. Tao X. Crystallographic investigations into properties of acentric hybrid perovskite single crystals NH(CH3)3SnX3 (X = Cl, Br).Chem. Mater. 2016; 28: 6968-6974Crossref Scopus (42) Google Scholar, 56He L. Gu H. Liu X. Li P. Dang Y. Liang C. Ono L.K. Qi Y. Tao X. Efficient anti-solvent-free spin-coated and printed Sn-perovskite solar cells with crystal-based precursor solutions.Matter. 2020; 2: 167-180Abstract Full Text Full Text PDF Scopus (7) Google Scholar, 57Dang Y. Liu Y. Sun Y. Yuan D. Liu X. Lu W. Liu G. Xia H. Tao X. Bulk crystal growth of hybrid perovskite material CH3NH3PbI3.CrystEngComm. 2015; 17: 665-670Crossref Google Scholar Low-dimensional perovskites with desired shapes are also obtained by either directly using the droplet of the reaction solution on the substrates or the spin-coating method.58Zhu L. Zhang H. Lu Q. Wang Y. Deng Z. Hu Y. Lou Z. Cui Q. Hou Y. Teng F. Synthesis of ultrathin two-dimensional organic-inorganic hybrid perovskite nanosheets for polymer field effect transistors.J. Mater. Chem. C. 2018; 6: 3945-3950Crossref Google Scholar, 59Ma D. Xu Z. Wang F. Deng X. Syntheses of two dimensional propylammonium lead halide perovskite microstructures by a solution route.CrystEngComm. 2019; 21: 1458-1465Crossref Google Scholar, 60Dou L.-T. Wong A.B. Yu Y. Lai M.L. Kornienko N. Eaton S.W. Fu A. Bischak C.G. Ma J. Ding T.N. et al.Atomically thin two dimensional organic-inorganic hybrid perovskites.Science. 2015; 349: 1518-1521Crossref PubMed Scopus (0) Google Scholar However, few synthesis and growth methods for chiral halide perovskites have been demonstrated. Although all synthetic methods use solutions such as dimethylformamide (DMF)/dimethyl sulfoxide (DMSO) or acid HX (X = Cl, Br, I) solution as solvent or require intentional heating, Wang et al. demonstrated the simple aqueous synthesis method to directly synthesize 1D and 2D perovskite single crystals at room temperature.61Wang J. Fang C. Ma J. Wang S. Jin L. Li W. Li D. Aqueous synthesis of low-dimensional lead halide perovskites for room-temperature circularly polarized light emission and detection.ACS Nano. 2019; 13: 9473-9481Crossref PubMed Scopus (11) Google Scholar By controlling the proper reaction conditions, different-dimensional halide perovskite single crystals can be formed with a high yield and excellent reproducibility (Figure 5). The control of pH value is important in this synthesis process. When adding the mixed MA/R-NH3 solution, the mixed aqueous solution by constant stirring results in a gradual increase in the pH value from below 1. 1D and 2D perovskite single crystals were formed with pH value of the solution below 4. When the pH value was higher than 4, the formation of a milk-white precipitate Pb(OH)2 was observed. Therefore, it is vital to control the pH of the reaction solution to obtain chiral halide perovskite crystals with different morphology in the halide perovskite systems. The slow evaporation method is vital for obtaining the single crystals commonly used for single-crystal structure analysis. Yao et al. reported the (R)- and (S)-MBA4Cu4I4 single crystals and their circularly polarized emission properties.62Yao L. Niu G. Li J. Gao L. Luo X. Xia B. Liu Y. Circularly polarized luminescence from chiral tetranuclear copper(І) iodide clusters.J. Phys. Chem. Lett. 2020; 11: 1255-1260Crossref PubMed Scopus (5) Google Scholar Chiral hybrid powder samples were easily obtained by combining CuI with chiral R- or S-MBA in ethanol at room temperature. (R-MBA)4Cu4I4 and (S-MBA)4Cu4I4 single crystals can also be formed by setting aside the precursor solution overnight (Figure 6A). In contrast, for traditional chiral materials, efforts have been made to design complicated chiral complexes, but this typically requires three or more steps and elaborate control over reaction and purification conditions. Determined from SXRD, the Cu-I cluster isomers have chemical formulas of (R-MBA)4Cu4I4 and (S-MBA)4Cu4I4, respectively. Both (R-MBA)4Cu4I4 and (S-MBA)4Cu4I4 crystallize into the orthorhombic chiral space group of P212121, and their crystalline structures are shown in Figures 6B and 6C. Therefore, this method is simple and reliable for obtaining small-sized chiral halide perovskite single crystals. The temperature-lowering method is suitable for halide perovskite crystal growth influenced by growth temperature. Bulk single crystals can be obtained by dipping the preferred seed into the acid solution. According to the different fixed positions of the seed crystals, bottom-seeded solution growth and top-seeded solution growth methods were demonstrated.54Dang Y. Zhou Y. Li