[(Ba₁₉Cl₄)(Ga₆Si₁₂O₄₂S₈)]: a Two-Dimensional Wide-Band-Gap Layered Oxysulfide with Mixed-Anion Chemical Bonding and Photocurrent Response

Abstract

Mixed-anion compounds play an essential part in modern structural chemistry. In this Communication, an unprecedented hexanary oxysulfide, [(Ba19Cl4)­(Ga6Si12O42S8)] (FJ-1), was synthesized at 1073 K by a standard solid-state method, which is a new phase in the AE/MIII/MIV/O/Q/X (AE = alkaline-earth metal; MIII = group 13 metal; MIV = group 14 metal; Q = chalcogen; X = halogen) system. FJ-1 adopts a new structure type and crystallizes in the orthorhombic system with space group Cmcm. In the structure, unique two-dimensional [Ga6Si12O42S8]34– layers formed by the familiar [SiO4] species and unusual heteroligand [GaO2S2] and [GaO3S] tetrahedra extend the intralayer linking. Significantly, a photoelectrochemical test revealed that FJ-1 is photoresponsive under ultraviolet illumination. Moreover, density functional theory calculations were employed to gain insight into the relationship between the electronic structure and optical properties. Such work will be conducive to the structural diversity of gallium coordination chemistry by exploration of the new mixed-anion functional chalcohalides.

Structural Transformation and Second-Harmonic-Generation Activity in Rare-Earth and d0 Transition-Metal Oxysulfides RE3NbS3O4 (RE = Ce, Sm, Gd, Dy)

“…In recent decades, many oxysulfides have been synthesized. On the basis of MQ 4 (M = Si, Ga, Ge; Q = S, O) units, a series of melilite-type oxysulfides and derivates like Sr 2 ZnGe 2 S 6 O, BaGeS 2 O, Sr 5 Ga 8 O 3 S 14 , Ba 2 In 2 Si 3 O 10 S, and [(Ba 19 Cl 4 )­(Ga 6 Si 12 O 42 S 8 )] have been found. In addition, it can be found that most oxysulfides contain transition metals such as Ba 5 (VO 2 S 2 ) 2 (S 2 ) 2 , Cd 2 Nb 2 O 7– x S x , and BiMOQ (M = Cu, Ag; Q = S, Se, Te) .…”

AIn4S6Cl (A = Rb and Cs) and Pb5Sn3Q10Cl2 (Q = S and Se): quaternary chalcohalides with mixed anionic coordination exhibit photocurrent responses

“…S6 †). The photocurrents of 1 and 2 are weaker than those of [(Ba 19 Cl 4 )(Ga 6 Si 12 O 42 S 8 )] (150 nA cm −2 ), 11 Lu 5 GaS 9 (150 nA cm −2 ) 44 and BaCuSbSe 3 (83 nA cm −2 ) 47 but stronger than those of Yb 6 Ga 4 S 15 (50 nA cm −2 ) 44 and BaCuSbS 3 (55 nA cm −2 ). 47 The cycle time intervals of 3 and 4 are 500 s and 20 s, respectively.…”

“…9 Rb 2 CdBr 2 I 2 with mixedanionic [CdBr 2 I 2 ] 2− tetrahedra exhibits promising comprehen-sive NLO performances including a wide band-gap of 3.35 eV, large SHG intensity, and a wide transparency range. 10 In addition, salt-inclusion chalcogenides [A a X b ][M c Q d ] (A: alkali, alkaline earth, and rare earth metals; X: halogen; M: d-or spblock elements; and Q: chalcogen) are an important subclass of mixed-anionic compounds and present properties such as photocurrent response, 11 thermoelectricity, 12 piezoelectricity, 13 phase transition 14 and NLO efficiency. 3,4,6 The abundant physical properties of mixed-anionic compounds mainly originate from their structural diversities since variable coordination environments with mixed anions and controllable structure frameworks can be formed.…”

“…For example, a Ga 3+ cation in [(Ba 19 Cl 4 )(Ga 6 Si 12 O 42 S 8 )] is tetrahedrally coordinated by two O 2− and two S 2− anions and the compound shows a large bandgap of 4.65 eV and a good photocurrent response of 150 nA cm −2 . 11 To the best of our knowledge, there is no report on the photocurrent response of a compound with cations coordinated by aliovalent anions.…”

Ba3HgGa2S7: A Zero-Dimensional Quaternary Sulfide Featuring a Unique [Hg2Ga4S14]12– String and Exhibiting a High Photocurrent Response

“…Inspired by the diverse applications of mixed-cation inorganic chalcogenides, we investigated the photocurrent properties of BHGS. Photocurrent measurement is usually utilized to evaluate the ability to transfer photoinduced electrons to the surface of materials. − Oxides, sulfides, oxysulfides, and oxyhalides have been continuously explored in optoelectronics (Table S7). When light was kept on, the photocurrent of BHGS reached to ∼12.2 μA/cm 2 (Figure ).…”