Ligand-Hole in [SnI6] Unit and Origin of Band Gap in Photovoltaic Perovskite Variant Cs2SnI6

Xiao, Zewen; Lei, Hechang; Zhang, Xiao; Zhou, Yuanyuan; Hosono, Hideo; Kamiya, Toshio

doi:10.1246/bcsj.20150110

Cited by 145 publications

(132 citation statements)

References 26 publications

Supporting

Mentioning

109

Contrasting

Order By: Relevance

“…Among the many A 2 BX 6 compounds, [96][97][98][99] A 2 SnI 6 (A = Cs, MA), [100][101][102][103][104][105][106][107][108][109] Cs 2 PdBr 6 , [110,111] and Cs 2 TiBr 6 [112,113] have been investigated for photovoltaic applications. As the [BX 6 ] octahedra in A 2 BX 6 compounds are isolated, the optoelectronic properties of these compounds are rather different from those of 3D ABX 3 (B = Pb, Sn, and Ge) halide perovskites.…”

Section: D a 2 B(iv)x 6 Perovskite Variantsmentioning

confidence: 99%

“…This leads to rather large m h for these compounds, particularly, along the Γ−X direction. [101] However, the transition from the VBM to the CBM is dipole-forbidden. Despite the isolation of [BX 6 ] octahedra, the CBMs are relatively dispersive, due to the charge redistribution of the B cations.…”

Section: D a 2 B(iv)x 6 Perovskite Variantsmentioning

confidence: 99%

“…[121,129,130] Park et al [131] first examined 0D A 3 Bi 2 I 9 (A = Cs, MA) nonperovskites as light absorbers in solar cells with the regular mesoporous structure, where the A 3 Bi 2 I 9 films were prepared using the typical one-step spin coating method. [101] Copyright 2015, The Chemical Society of Japan. Since then, many efforts have been devoted to improving the performance of 0D A 3 Bi 2 X 9 -based solar cells.…”

Section: D a 3 B(iii) 2 X 9 Nonperovskites (Dimer Phases)mentioning

confidence: 99%

See 2 more Smart Citations

From Lead Halide Perovskites to Lead‐Free Metal Halide Perovskites and Perovskite Derivatives

2019

Self Cite

View full text Add to dashboard Cite

serious challenges due to the inclusion of toxic Pb and instability against moisture, heat, and irradiation. In recent years, significant efforts have been paid to develop Pb-free halide perovskite and perovskite derivative absorber materials. However, so far, solar cells based on these materials show significantly inferior performances as compared to their Pb halide perovskite counterparts. Herein, we provide reviews on the fundamental understandings of the photovoltaic properties from Pb halide perovskites to Pb-free metal halide perovskites and perovskite derivatives as well as the experimental results reported in the literature. The results suggest that replacing Pb by nontoxic elements may degrade the superior photovoltaic properties seen in Pb halide perovskites, explaining the fact that all reported solar cells based on Pb-free perovskites or perovskite derivatives show performances significantly lower than Pb halide perovskite solar cells. Overview: Approaches and Consequences of Pb ReplacementWe first provide an overview of the approaches and consequences of Pb replacement reported in the literature, as shown in Figure 1. In general, there are two categories for Pb replacement: using either homovalent elements such as Sn and Ge or heterovalent elements such as Bi and Sb. The heterovalent replacement category can be divided into two subcategories based on the ways to maintain the charge neutrality: ion-splitting and ordered vacancy. The ion-splitting subcategory can be further divided into mixed anion compounds with the formula of AB(Ch,X) 3 , where Ch represents a chalcogen element, and X represents a halogen element, and mixed cation compounds with a formula of A 2 B(I)B(III)X 6 , which are commonly called double perovskites. The ordered vacancy subcategory can also be divided into the B(III) compounds with a formula of A 3 ◻B(III)X 9 and the B(IV) compounds with a formula of A 2 ◻ B(IV)X 6 (the sign of ◻ indicates vacancy). Figure 1 also summarizes the photovoltaic properties and the stabilities of each group of materials, which provides a clear overview of the consequences of Pb replacement. While the homovalent replacement by Sn or Ge leads to instability, the heterovalent Pb replacement leads to degraded electronic properties mainly due to the reduction on electronic dimensionality. As a result, all the reported Pb-free perovskite and perovskite derivative solar Despite the exciting progress on power conversion efficiencies, the commercialization of the emerging lead (Pb) halide perovskite solar cell technology still faces significant challenges, one of which is the inclusion of toxic Pb. Searching for Pb-free perovskite solar cell absorbers is currently an attractive research direction. The approaches used for and the consequences of Pb replacement are reviewed herein. Reviews on the theoretical understanding of the electronic, optical, and defect properties of Pb and Pb-free halide perovskites and perovskite derivatives are provided, as well as the experimental results available in the literature....

show abstract

Section: D a 2 B(iv)x 6 Perovskite Variantsmentioning

confidence: 99%

Section: D a 2 B(iv)x 6 Perovskite Variantsmentioning

confidence: 99%

Section: D a 3 B(iii) 2 X 9 Nonperovskites (Dimer Phases)mentioning

confidence: 99%

See 1 more Smart Citation

From Lead Halide Perovskites to Lead‐Free Metal Halide Perovskites and Perovskite Derivatives

2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…On the other hand, Cs2SnI6 have not shown p-type conductivity unlike the other Sn 2+ -based compounds and have shown ntype conduction or insulating behavior depending on the synthetic routes. Lee et al 13 reported the native n-type conduction with electron density (n) of ~110 14 cm 3 in polycrystalline Cs2SnI6 pellets annealed at 200 o C, while Zhang et al 18 observed very high resistivity in room temperature-processed Cs2SnI6. Therefore, in order to clarify the intrinsic nature of Cs2SnI6 and its origin, a systematic theoretical study on the intrinsic defects is important, which will provide a guiding principle for tuning its properties for photovoltaic and other semiconductor applications.…”

Section: +mentioning

confidence: 99%

Intrinsic defects in a photovoltaic perovskite variant Cs₂SnI₆

Xiao

Zhou

Hosono

et al. 2015

Phys. Chem. Chem. Phys.

Self Cite

209

230

View full text Add to dashboard Cite

Cs2SnI6 is a variant of perovskite materials and is expected as a lead-free air-stable photovoltaic material. In this letter, we report intrinsic defects in Cs2SnI6 using first-principles density functional theory calculations. It is revealed that iodine vacancy and tin interstitial are the dominant defects that are responsible for the intrinsic n-type conduction in Cs2SnI6. Tin vacancy has a very high formation energy (>3.6 eV) due to the strong covalency in the SnI bonds and is hardly generated for ptype doping. All the dominant defects in Cs2SnI6 have deep transition levels in the band gap. It is suggested that the formation of the deep defects can be suppressed significantly by employing an I-rich synthesis condition, which is inevitable for photovoltaic and other semiconductor applications.Metal halide perovskites have been introduced as the "gamechanger" materials in the novel solid-state solar cells.1-4 These perovskite compounds have the general chemical formula ABX3 (A = Cs, CH3NH3, or CH2NH=CH; B = Pb or Sn; X = I, Br or Cl), where the A cations sit in the cubic or pseudo-cubic network of corner-sharing BX6 octahedra (see Fig. 1a). Among these materials, tin (Sn) based perovskites ASnX3 have attracted particular interest due to their nontoxicity. [5][6][7][8][9] However, ASnX3 are very sensitive to the ambient atmosphere (oxygen, moisture, etc.) [7][8][9][10][11][12] and exploration for air-stable alternatives has become an urgent issue. Promisingly, Lee et al. 13 recently reported that the Sn-based perovskite variant Cs2SnI6 exhibited high air-stability and their solar cells exhibit good efficiently as high as 8%. It is proposed that the superior stability of Cs2SnI6 to CsSnI3 would be attributed to the +4 oxidation state of Sn in Cs2SnI6 based on a simple ionic model;13 on the other hand, density functional / hybrid density functional theory (DFT/HDFT) calculations indicate that the real oxidation state of Sn in Cs2SnI6 is closer to +2, similar to CsSnI3, which originates from the nominal formula Cs + 2Sn 2+ I6 4-. 14 In this view, the improved stability of Cs2SnI6 is attributed to the strong covalency of the Sn-I bonds in the isolated [SnI6] 2-cluster.It is known well that the typical Sn 2+

show abstract

“…The examples includes h-BN, MoS 2 (Figures 3b and 3c). 113116 The yields of product using this route are high and yields over 90% for MoS 2 and TaS 2 nanosheets have been reported.…”

mentioning

confidence: 99%

Two-Dimensional (2D) Nanomaterials towards Electrochemical Nanoarchitectonics in Energy-Related Applications

Khan

Ghosh

Pradhan

et al. 2017

Bulletin of the Chemical Society of Japan

398

197

View full text Add to dashboard Cite

includes self-assembled fullerene crystals design from zero-to-higher dimensions, mesoporous fullerene crystals and their conversion into graphitic mesoporous carbons, high surface area nanoporous carbon material design from agro-waste for electrochemical supercapacitors and VOC adsorption. Somobrata AcharyaSomobrata Acharya received his Ph.D. degree from Jadavpur University, India. He is currently Associate Professor in the Centre for Advanced Materials (CAM), Indian Association for the Cultivation of Science (IACS), India. He is carrying out research in interdisciplinary areas probing structure-property relationship and possible applications of semiconductor nanomaterials in the areas of energy generation and consumption. His research area includes heterostructures, 2D nanostructures, superlattices, supramolecular assemblies and their suitable applications. Katsuhiko ArigaKatsuhiko Ariga received his Ph.D. degree from Tokyo Institute of Technology. He is currently the Director of Supermolecules Group and Principal Investigator of World Premier International (WPI) Research Centre for Materials Nanoarchitectonics (MANA), the National Institute for Materials Science (NIMS). His research is oriented to supramolecular chemistry, surface science, and functional nanomaterials (Langmuir-Blodgett film, layer-by-layer assembly, self-organized materials, sensing and drug delivery, molecular recognition, mesoporous material, etc. and he is now trying to combine them into a unified field. AbstractDesigning nanoscale components and units into functional defined systems and materials has recently received attention as a nanoarchitectonics approach. In particular, exploration of nanoarchitectonics in two-dimensions (2D) has made great progress these days. Basically, 2D nanomaterials are a center of interest owing to the large surface areas suitable for a variety of surface active applications. The increasing demands for alternative energy generation have significantly promoted the rational design and fabrication of a variety of 2D nanomaterials since the discovery of graphene. In 2D nanomaterials, the charge carriers are confined along the thickness while being allowed to move along the plane. Owing to the large planar area, 2D nanomaterials are highly sensitive to external stimuli, a characteristic suitable for a variety of surface active applications including electrochemistry. Because of the unique

show abstract

Ligand-Hole in [SnI6] Unit and Origin of Band Gap in Photovoltaic Perovskite Variant Cs2SnI6

Cited by 145 publications

References 26 publications

From Lead Halide Perovskites to Lead‐Free Metal Halide Perovskites and Perovskite Derivatives

From Lead Halide Perovskites to Lead‐Free Metal Halide Perovskites and Perovskite Derivatives

Intrinsic defects in a photovoltaic perovskite variant Cs₂SnI₆

Two-Dimensional (2D) Nanomaterials towards Electrochemical Nanoarchitectonics in Energy-Related Applications

Contact Info

Product

Resources

About

Ligand-Hole in [SnI6] Unit and Origin of Band Gap in Photovoltaic Perovskite Variant Cs2SnI6

Cited by 145 publications

References 26 publications

From Lead Halide Perovskites to Lead‐Free Metal Halide Perovskites and Perovskite Derivatives

From Lead Halide Perovskites to Lead‐Free Metal Halide Perovskites and Perovskite Derivatives

Intrinsic defects in a photovoltaic perovskite variant Cs2SnI6

Two-Dimensional (2D) Nanomaterials towards Electrochemical Nanoarchitectonics in Energy-Related Applications

Contact Info

Product

Resources

About

Intrinsic defects in a photovoltaic perovskite variant Cs₂SnI₆