Cation Substitution of Hexagonal Triple Perovskites: A Case in Trimetallic Tellurates A₂A′BTe₂O₉

Abstract

Three new tellurates, namely, K 2 BaPb 0.62 Ba 0.38 Te 2 O 9 (1), Rb 2 BaPb 0.7 Ba 0.3 Te 2 O 9 (2), and Ba 2 KLiTe 2 O 9 (3), with hexagonal triple-perovskite structures have been designed via a cation substitution strategy. All three centrosymmetric compounds crystallize in the same hexagonal space group P6 3 /mmc. In their structures, the [BTe 2 O 9 ] (B = Pb/Ba for 1 and 2 and Li for 3) groups construct the final threedimensional framework using face-sharing [Te 2 O 9 ] dimmers and vertex-linked [BO 6 ] linkages. Meanwhile, the theoretical calculations demonstrate the numerical differences of their birefringence. Thermal stability analysis and differential scanning calorimetry were performed, and UV−vis−NIR diffuse reflectance spectra and infrared spectra of the three title compounds were also characterized and analyzed.

Lead Tellurite Crystals BaPbTe2O6 and PbVTeO5F with Large Nonlinear-/Linear-Optical Responses due to Active Lone Pairs and Distorted Octahedra

“…The optical band gap values of BaPbTe 2 O 6 and PbVTeO 5 F are 3.65 and 2.22 eV, respectively, according to the Kubelka–Munk function on the basis of the spectral data. BaPbTe 2 O 6 and PbVTeO 5 F have optical band gap values of 3.65 and 2.22 eV, respectively, suggesting that both compounds have evidently different band gaps, which are comparable to those of reported compounds such as K 2 BaPb 0.62 Ba 0.38 Te 2 O 9 (3.3 eV), Pb 4 B 6 O 13 (3.21 eV), Ba 4 B 8 TeO 19 (3.42 eV), Rb 2 VO­(O 2 ) 2 F (2.81 eV), and PbTa 2 V 2 O 11 (2.24 eV) …”

The optical research progress of nanophosphors composed of transition elements in the fourth period of near-infrared windows I and II for deep-tissue theranostics

“…88 Nevertheless, it faces severe problems that limit its power conversion efficiency due to the absorption mismatch between sensitizers in cells and the solar irradiation spectrum. 89 An improvement in the light capture ability is necessary to boost the efficiency of DSC. Novel photoelectrode materials containing NIR nanophosphors are appropriate candidates for optimizing the performance of DSCs.…”

Synthesis, structure and characterization of Cd2TeO3Cl2 with unprecedented [Cd2O6Cl4] octahedral dimers

“…[23][24][25][26][27] Compared to fluorooxoborates, fluorophosphates and fluorooxosilicates, [28][29][30][31] heavy metal oxide halides like Pb 17 O 8 Cl 18 , 32 Sn 14 O 11 Br 6 , 33 Sb 5 O 7 I 34 and CdPbOCl 2 35 usually show a wide infrared (IR) transparency region that is important for IR optical materials. [36][37][38] Compared with metal elements, tellurium(IV) can form a variety of low-coordinated motifs, such as trigonal pyramidal [TeO 3 ], seesaw [TeO 4 ], and square pyramidal [TeO 5 ], [39][40][41] due to the relatively close orbital energies of Te 5s and 5p. [42][43][44] Hence, combining heavy metal oxide halides with Te-containing oxides could be a feasible way to develop new functional materials, and a great number of experimental investigations have been implemented in metal tellurate oxide halide systems.…”

“…Compared with metal elements, tellurium( iv ) can form a variety of low-coordinated motifs, such as trigonal pyramidal [TeO 3 ], seesaw [TeO 4 ], and square pyramidal [TeO 5 ], 39–41 due to the relatively close orbital energies of Te 5 s and 5 p . 42–44 Hence, combining heavy metal oxide halides with Te-containing oxides could be a feasible way to develop new functional materials, and a great number of experimental investigations have been implemented in metal tellurate oxide halide systems.…”