JOURNAL OF ALLOYS AND COMPOUNDS
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2014
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IF 2.726
Wenlong Yin,Kai Feng,Lei Kang,Bin Kang,Jianguo Deng,Zheshuai Lin,Jiyong Yao,Yicheng Wu
The first two members in the quaternary A/A′/M/Q (A = alkali metal; A′ = alkaline-earth metal; M = As, Sb, Bi; Q = S, Se, Te) system, namely the KBaMSe 3 (M = As, Sb) selenides, have been synthesized by solid state reactions. They are isostructural and crystallize in the centrosymmetric space group P 2 1 / c of the monoclinic system. In the structure, the trivalent M atom (M = As, Sb) is coordinated to three Se atoms forming a trigonal pyramid with the Se atoms serving as the triangle base, showing the stereochemical activity of the ns 2 lone pair electron. The MSe 3 (M = As, Sb) trigonal pyramids are totally isolated from each other with K + and Ba 2+ cations located between them. The optical band gaps of 2.26 (2) eV for KBaAsSe 3 and 2.04 (2) eV for KBaSbSe 3 , were deduced from the diffuse reflectance spectra. The first principles calculations were performed to study the electronic structures of KBaMSe 3 (M = As, Sb) compounds and the results indicated that these two compounds are indirect band gap semiconductors.
研究领域:
材料科学
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化学
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DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2021
·
IF 2.328
Fanggong Cai,Xiaobo Lei,Jiao Geng,Wei Sun,Jun Chen,Sude Ma,Qinyong Zhang
The homologous Pb m Bi 2n X m+3n (X = S, Se, Te) is expected as solar cells or thermoelectric materials. Herein, stable phases of ternary PbBi 2 S 4 microspheres were successfully synthesized by two solution-phase-methods assisting with EDTA-2Na in aqueous media, namely traditional chemical reaction under atmospheric pressure and hydrothermal method under high pressure. Field-emission scanning electron microscopy and X-ray diffraction were used to characterize and determine the morphology and structure of the product. EDTA-2Na plays critical roles in the crystallization process of uniform PbBi 2 S 4 microspheres. A mechanistic model is proposed to account for these experimental findings. Furthermore, the optical band gaps of PbBi 2 S 4 were investigated as well.
研究领域:
材料科学
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化学
✓ 已验证
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DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2019
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IF 2.12
Peng Ren,Yun Yang,Shilie Pan
The new oxychloride, Ba 27 Pb 8 O 8 Cl 54 , has been synthesized by a high temperature solution method. It crystallizes as cubic brown block with unit-cell a = 22.547(2), space group Fm 3 ¯ m (No. 225). It features a complicated three-dimensional network composed of [Ba 20 O 4 Cl 92 ] and [Ba 14 O 8 Cl 36 ] units sharing one Ba atom and its coordination atoms, which is inserted by new isolated [Pb 4 O 4 ] clusters. The UV–Vis-IR diffuse reflectance spectrum exhibits that its optical band gap is about 3.9 eV. In this paper, the structural features, thermal behaviors and optical properties were systemically studied.
研究领域:
材料科学
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化学
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DOI
高影响因子
OPTIK
·
2022
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IF 2.84
Ruoxian Hou,Hanzhang Chen,Defu Sun,Nana Zhang,Chuanying Shen,Duanliang Wang
Using the solvent evaporation approach at room temperature (RT), we produced transparent single crystals of two new organic-inorganic hybrid materials: (C 5 H 6 NO)SO 3 NH 2 (crystal 1: reaction by sulfamate and 4-hydroxypyridine) and (C 3 H 5 N 2 )SO 3 NH 2 (crystal 2: reaction by sulfamate and imidazole). Both crystals have the same space structure and belong to the P 2 1 / c space group of the monoclinic crystal system, according to the results of X-ray single crystal diffraction. In crystals 1 and 2, sulfamic acid and organics (4-hydroxypyridine, imidazole) are alternatively positioned by hydrogen bonds to create a layered structure. Hydrogen bonds and electrostatic Coulomb forces connect the layers to one another. Powder XRD demonstrates the remarkable phase purity of both crystals. Furthermore, the optical properties of both crystals, including IR , UV absorption, and fluorescence spectra , have been investigated in detail. The presence of functional groups such as NH 2 and C C in the grown crystals was confirmed by Fourier transform infrared analysis. The optical band gaps for crystals 1 and 2 are about 4.33 and 4.31 eV, respectively, and the UV absorption findings show a low light absorption . According to the photoluminescence spectra, the two crystals have distinct fluorescence characteristics, with emission peaks of approximately 433 nm and 442 nm, apiece.
研究领域:
材料科学
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光学
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DOI
高影响因子
POWDER DIFFRACTION
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2020
·Vol. 35
·期 4
·276-281
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IF 0.919
Shengru Wang,Xiaofang Lai,Bingsheng Du,Junhao Ma,Peihua Wang,Jikang Jian
In this work, SnS1−xSex ternary nanobelts were synthesized by a facile hydrothermal method without the assistance of surfactants. The structure, morphology, microstructure, compositions, chemical valences, phonon modes, and optical band gaps of the SnS1−xSex nanobelts were characterized in detail. The results indicate that the SnS1−xSex nanobelts have uniform one-dimensional morphology and are single crystals with high crystallinity. Se is incorporated into the SnS lattice to substitute for S-forming ternary SnS1−xSex alloy. With the increase of Se doping concentration, the optical band gaps of the nanobelts gradually decrease from 1.15 to 1.01 eV, confirming the tunable optical property achieved here.
研究领域:
材料科学
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光学
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DOI
高影响因子
DALTON TRANSACTIONS
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2021
·Vol. 50
·期 45
·16562-16567
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IF 4.39
Ru-Ling Tang,Xin Lian,Wen-Dong Yao,Wenlong Liu,Sheng-Ping Guo
Metal halides have potential applications in many optics-related fields, such as birefringence materials. Here, a pentanary fluoride K3Na(TaF7)(SiF6) has been obtained through a facile hydrothermal route. It crystallizes in the orthorhombic space group Immm, and its zero-dimensional framework features isolated SiF6 octahedra and TaF7 monocapped trigonal prisms, a new type of combination representing a new structure-type. It exhibits two wide optical band gaps of 4.46 eV and 5.67 eV which is consistent with DFT calculation. K3Na(TaF7)(SiF6) exhibits a larger birefringence (0.045 at 253.7 nm) compared with the commercial MgF2 crystal.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2018
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IF 4.7
Yibao Chen,Maxim S. Molokeev,Victor V. Atuchin,Ali H. Reshak,Sushil Auluck,Zeyad A. Alahmed,Zhiguo Xia
Exploring new perovskite-related solid-state materials and the investigating composition-dependent structural and physical properties are highly important for advanced functional material development. Herein, we present the successful hydrothermal synthesis of tetragonal CsPb2Cl5 and the anion-exchange phase formation of CsPb2(Cl1–xBrx)5 (x = 0–1) solid solutions. The CsPb2(Cl1–xBrx)5 crystal structures, which crystallize in the tetragonal system, space group I4/mcm, with parameters similar to those of CsPb2Cl5, have been determined by Rietveld analysis. The optical band gap was obtained by UV–vis spectroscopy, and the band structure was further calculated by the full-potential method within the generalized gradient approximation. It was revealed that the band gap in CsPb2(Cl1–xBrx)5 solid solutions can be tuned over the range of 4.5–3.8 eV by anion substitution.
研究领域:
材料科学
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物理化学
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DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
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2020
·Vol. 22
·期 9
·1-11
·
IF 2.132
Wang Wei,Zhi Guowei,Liu Jijinhua,Hao Lingyun,Yang Lu,Zhao Yijie,Hu Yingfei
In the paper, the effects of polyvinylpyrrolidone (PVP) concentration and chemical wet etching on morphologies and phase composition of CuSbS 2 particles synthesized by microwave irradiation method were investigated. The phase structure, morphologies, and optical and photocatalytic properties were analyzed by using characterization techniques. The results showed that the morphology of as-prepared particles was spherical and the shape of particles etched in Na 2 S solution was tetragonal rod-like structure. The optical band gap of the particles with 1.5 g PVP after chemical etching was about 1.41 eV. The photocatalytic performance of CuSbS 2 could be significantly improved after Na 2 S chemical etching. The amounts of PVP had an obvious influence on specific surface area of as-synthesized CuSbS 2 particles. The CuSbS 2 particles with 1.5 g PVP had the best photocatalytic performance after chemical etching treatment, and the C / C 0 value reached 0.36.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Xue Zhang,Guoshuai Li,Feng Mao,Dongdong Han,Chengbin Jing,Ye Chen,Pingxiong Yang,Junhao Chu,Fangyu Yue
Doping- and temperature-induced phase transitions and optical/electric-properties for (1- x )KNbO 3 - x (Ba 0.5 Bi 0.5 )(Nb 0.5 Zn 0.5 )O 3 ceramics are studied. With the increase of x -value, a series of structural phase transitions from orthorhombic to tetragonal and to cubic is observed, and the phase transition temperatures are also improved for forming a stable phase. The deteriorated ferroelectric property , which also suggests the doping-induced phase transition due to the enhancement of the crystal symmetry , can be tentatively interpreted from the optical evolution with doping. This doping can introduce or enhance the bandedge- or in-gap states but without influence upon the optical bandgap of KNbO 3 . These results help in understanding the control of the structure, optical and electrical properties in KNbO 3 -based ferroelectric oxides.
研究领域:
材料科学
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物理学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Kang Cheng,Weichao Huang,Xinyue Liu,Xinyong Gong,Chaoyong Deng
ABSTRACT Broadband near-infrared spectroscopy has become a research hotspot because it can be used in many fields. For the preparation of near-infrared phosphors, non-toxic and harmless Fe 3+ is an excellent activator. Herein, Fe 3+ -activated NaAl 5 O 8 near-infrared phosphors were prepared, the phase and the properties of luminescence were analyzed. Under the excitation of 346 nm, the NaAl 5 O 8 :Fe 3+ phosphors emit 600–850 nm light, 754 nm is the emission peak of the sample. The optical band gap of NaAl 5 O 8 :Fe 3+ was evaluated. It was observed that the optical band gap of sample narrows as the doping concentration of Fe 3+ increases. By measuring the emission spectra at 303–463 K, it is evident that the emission intensity remains 83.1 % of 303 K at 423 K. It shows that the thermal stability of the sample is good. The luminescence of the sample after soaking in deionized water for 0–10 h were observed. These results indicate that the NaAl 5 O 8 :Fe 3+ samples have application prospects in some high temperature or wet fields. Moreover, the security ink was prepared by using NaAl 5 O 8 :Fe 3+ , indicating that the sample can be used in the field of anti-counterfeiting.
研究领域:
材料科学
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光学
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DOI
高影响因子
SOLID STATE SCIENCES
·
2024
·
IF 3.4
Renzhong Xue,Liuyang Zhao,Xiaosong Liu,Haiyan Wang,Xiang Zhu,Yifan Xiao,Chunyu Yuan,Binbin Cao,Ziyang Chen,Tao Li,Haiyang Dai
In this paper, Ta-doped Bi 2/3 Cu 3 Ti 4 O 12 (BCTO) ceramics are prepared by solid-state method. Phase structure, microstructure, optical, dielectric, and non-Ohmic properties of all samples are systematically investigated. Cu/Ta-rich phases at grain boundaries (GB) together with defects affect the microstructure, causing grain size and compactness to increase first and then decrease. Moreover, Ta doping increases the optical band gap of BCTO from 4.03 to 4.25 eV as well as the GB activation energy and GB barrier. An increase in dielectric constant (Ɛ r ), nonlinear coefficient (α) and breakdown field (E b ), and a decrease in the dielectric loss (tanδ) are observed in Ta-doped BCTO ceramics. The improvement in dielectric and non-Ohmic properties can be attributed to the internal barrier layer caused by GB Schottky barrier structure. In particular, Bi 2/3 Cu 3 Ti 3.95 Ta 0.05 O 12 ceramic exhibits the high Ɛ r of ∼45997 and the low tanδ of ∼0.035 at 10 kHz along with α of ∼5.62, and E b of ∼3.45 kV/cm. The temperature-independent (-110-210 °C) dielectric response confirms that temperature stability of specimens increases with doping. These results suggest that improved optical, dielectric, and non-Ohmic properties in Bi 2/3 Cu 3 Ti 4 O 12 can be achieved simultaneously via defect engineering.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2020
·Vol. 31
·期 13
·10639-10648
·
IF 2.22
Si Shufang,Deng Hongmei,Wang Tiantian,Zheng Dongliang,Yang Pingxiong,Chu Junhao
Multiferroic ferrite–ferroelectric composites with general formula x CoFe 2 O 4 -(1 − x )K 0.5 Bi 0.5 TiO 3 ( x = 0.0, 0.3, 0.5, 0.7, and 1.0) ( x CFO-KBT) were developed by conventional solid-state reaction method. The structural, optical, magnetic and ferroelectric properties for the prepared samples were studied in detail. Two individual structures of spinel-type ferrite and tetragonal-type ferroelectric are characterized through X-ray diffraction while Raman scattering spectra and SEM analyses furtherly confirm the coexistence of the two phases in the composites. The bandgaps calculated for the composites narrow dramatically compared with the pure KBT, which are attributed to Co 2+ d–d on-site transitions from the CFO phase. The magnetic property transforms from diamagnetism for pure KBT to ferromagnetism for the composites and pure CFO with saturation magnetization M s increasing gradually with addition of CFO. Besides, the room temperature ferroelectricity has been detected in the composites, which turns out to be enhanced by space charge contribution of CFO phase. The improvement of optical and multiferroic properties in the composites indicates great prospect on visible-light optical devices and non-volatile data storage.
研究领域:
材料科学
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物理学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）