NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
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2017
·
IF 1.109
M.M. Mikhailov,V.V. Neshchimenko,C. Li,V.A. Vlasov
The effect on band gap (E g ) and crystal structure of ZnO modified by Al 2 O 3 , ZrO 2 , SiO 2 , CeO 2 , TiO 2 and Y 2 O 3 nanoparticles at concentrations less than 30 wt% has been investigated. Established that change of E g reach to 0.03 eV and determined by charge of cations and their radius, as well as the concentration of the nanoparticles. Lattice parameters changes at modifying by nanoparticles with a smaller and larger radius of cations than the ion Zn 2+ . Influence of 100 keV protons irradiation result in blue shift in absorption edge of polycrystalline zinc oxide modified by Al 2 O 3 , ZrO 2 , SiO 2 , CeO 2 , TiO 2 and Y 2 O 3 nanoparticles.
研究领域:
材料科学
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物理学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 47
·29378-29385
·
IF 3.108
Leyan Nian,Junben Huang,Kui Wu,Zhi Su,Zhihua Yang,Shilie Pan
Five non-centrosymmetric (NCS) quaternary metal chalcogenides, BaCu2SiSe4, BaCu2GeS4, BaCu2GeSe4, BaCu2SnS4, and BaCu2SnSe4, were successfully synthesized by solid-state reaction in vacuum-sealed silica tubes. They crystallized in the three different space groups: Ama2 for BaCu2SnSe4, P3121 for BaCu2GeS4 and BaCu2GeSe4, and P3221 for BaCu2SiSe4 and BaCu2SnS4. Note that BaCu2GeS4 and BaCu2GeSe4 show the mirror symmetrical structures to those of BaCu2SiSe4 and BaCu2SnS4. In comparison with their structures, it can be found that the [CuSe4] units are connected together to form a two-dimensional (2D) layer structure in BaCu2SnSe4, which is different from the 3D framework structure formed by the interlinked [CuQ4] (Q = S and Se) units in other four title compounds. In addition, BaCu2SnSe4 exhibits only one type of tunnel structure with the isolated [BaSe8] units existing in each tunnel, which is also different from the other title compounds (two types of tunnels with the isolated [BaSe8] units and [BaSe6]n chains located). The interesting structural changes also indicate that slight change of cation size would result in different structure features, and future structure prediction should devote considerable attention to the different chalcogen atoms. Moreover, important optical properties (optical bandgap, infrared (IR) absorption edge, second harmonic generation (SHG) response) of the title compounds were systematically investigated. Among them, IR and Raman spectra indicate that all of them exhibit the wide IR absorption edges (∼22 μm). Powder SHG measurement shows that BaCu2SnS4 possesses good SHG response about 1.6 times that of benchmark AgGaS2 (AGS) at the particle size 55–88 μm. All results indicate that BaCu2SnS4 can be expected as a potential IR nonlinear optical (NLO) candidate. Theoretical calculation was also used to analyze the structure–property relationship and their electronic structures and origin of NLO effect were studied in detail.
研究领域:
材料科学
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晶体学
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光学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2023
·
IF 3.8
Yanhui Zhang,Aixin Zhu,Hualing Tian,Xiaofeng Gu,Zhi Su
Two new alkali/alkaline-earth metal pyrophosphate fluorides, A 2 Mg 2 P 2 O 7 F 2 ( A = K , Rb) have been synthesized, structurally analyzed, and characterized for the first time. They both crystallize in the Pbcn space group and show similar crystal structures. Their structures contain 1 [M g 2 O 7 F 3 ] ∞ chains made up of edge-sharing MgO 4 F 2 octahedra and 2 [ A 2 O 11 F 4 ] ∞ layers built by face-sharing [ A 2 O 11 F 4 ] clusters, which are bridged by isolated P 2 O 7 units to construct a 3D framework. It's worth noting that A 2 Mg 2 P 2 O 7 F 2 ( A = K , Rb) are the first pyrophosphate fluoride in the A -Mg-P-O-F ( A = alkali metal) system. Furthermore, the optical measurements of the title compounds show that they all possess UV absorption cutoff edges. First-principles theoretical studies were conducted to understand the electronic structures.
研究领域:
无机化学
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材料科学
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理论计算
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2020
·Vol. 7
·期 14
·2669-2675
·
IF 5.958
Shunhang Wei,Xiaoxiang Xu
Nitrogen doping was applied to layered compound LaZrTa3O11 (a wide bandgap semiconductor photocatalyst). Bandgap reductions >2.2 eV were achieved by this modification, which effectively red-shifted the light-absorption edge of LaZrTa3O11 from 300 nm to ∼650 nm. Nitrogen-doped LaZrTa3O11 (i.e., LaZrTa3O11−xNy) was now active for both water-reduction and -oxidation reactions under visible-light illumination (λ ≥400 nm) with good durability and stability. An apparent quantum efficiency (AQE) as high as 0.53% at 420 ± 20 nm was achieved for water-oxidation reactions. Further analyses suggested that its visible-light activity originated mainly from an uplift of the valence band edge as a result of nitrogen incorporation. This strategy to achieve visible-light activity was very inspiring and could be applicable to other layered compounds that are active only under ultraviolet-light illumination.
研究领域:
材料科学
·
光化学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2021
·
IF 4.076
Yunqiao Guo,Die Zhang,Ting Zheng,Ling Huang,Daojiang Gao,Jian Bi,Guohong Zou
Two new alkali metal formic-borates named Rb3(COOH)3(H3BO3)2 and Cs3(COOH)3(H3BO3)2 have been successfully synthesized under mild conditions. Influenced by the different cation sizes, these two stoichiometrically equivalent compounds reveal discrepant symmetries: Rb3(COOH)3(H3BO3)2 is noncentrosymmetric (NCS) while Cs3(COOH)3(H3BO3)2 is centrosymmetric (CS). Especially, these two title compounds exhibit unique planar [(COOH)3(H3BO3)2]3– layers constructed from two kinds of planar π-conjugated asymmetric BO3 and COOH units, which induce the large birefringence, 0.09@1064 nm for Rb3(COOH)3(H3BO3)2 and 0.10@1064 nm for Cs3(COOH)3(H3BO3)2, respectively. Optical property measurements indicate that these two compounds display short UV absorption edges, suggesting that they are promising short-wave UV birefringent materials. A detailed theoretical analysis confirmed that the excellent linear optical property was derived from the synergistic effect of the two kinds of π-conjugated planar groups.
研究领域:
材料科学
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光学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
·
IF 5.316
Yawei Jiang,Yan Mi,Chufan Li,Wenjian Fang,Xiaochuan Li,Xianghua Zeng,Yongsheng Liu,Wenfeng Shangguan
The solid solution constructed by two or more semiconductors with different bandgaps can effectively modulate the energy band, satisfying the redox potential for both H + /H 2 and O 2 /H 2 O. In this paper, Sillen-Aurivillius compounds with layered structure Bi 3 O 4 Cl and Y 3 O 4 Cl solid solution (Bi 3−x Y x O 4 Cl) were successfully synthesized by the solid-phase method. The absorption edge of Bi 3−x Y x O 4 Cl could be dramatically changed from about 500–740 nm with the increase of Bi elements, which accounted for the entire UV-Vis region of the solar spectrum. Furthermore, the bandgaps for Bi 3−x Y x O 4 Cl could be adjusted from about 2.6–2.0 eV with the decreased Y/Bi ratio from 2 to 0.2. Significantly, the conduction band minimum energy (CBM) of Bi 3−x Y x O 4 Cl all satisfied the redox potential for H + /H 2 , which showed excellent visible-light photocatalytic water splitting.
研究领域:
材料科学
·
化学
·
光催化
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2013
·
IF 4.593
Xiang Xu,Chun-Li Hu,Fang Kong,Jian-Han Zhang,Jiang-Gao Mao,Junliang Sun
A new alkali-metal borogermanate with noncentrosymmetric structure, namely, Cs2GeB4O9, has been discovered, and a large crystal with dimensions of 20 × 16 × 8 mm3 has been grown by a high-temperature top-seeded solution method using Cs2O–B2O3 as a flux. The compound crystallizes in the tetragonal space group I4̅ with a = b = 6.8063(2) Å, c = 9.9523(7) Å, V = 461.05(4) Å3, and Z = 2. It features a three-dimensional anionic open framework based on GeO4 tetrahedra and B4O9 clusters that are interconnected via corner-sharing, forming one-dimensional channels of nine-/ten-membered rings along the a and b axes, which are occupied by Cs+ cations. Cs2GeB4O9 exhibits a very high thermal stability with a melting point of 849 °C, and it possesses a short-wavelength absorption edge onset at 198 nm determined by UV–vis transmission spectroscopy measurements on a slab of polished crystal. Powder second-harmonic generation (SHG) measurement on sieved crystals reveals that Cs2GeB4O9 is a type I phase-matchable material with a strong SHG response of about 2.8 × KH2PO4. The preliminary investigation indicates that Cs2GeB4O9 is a new promising second-order nonlinear-optical crystalline material.
研究领域:
材料科学
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非线性光学
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晶体生长
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固体化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
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2022
·Vol. 46
·期 47
·22895-22907
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IF 3.925
Sheng Chen,Ji-Nan He,Ying-Min Xu,Sheng-Li Chen,Ai-Jun Wang
Photocatalytic conversion of nitrogen to ammonia with water under ambient conditions is a desired strategy. In the present work, in order to increase the activity of the TiO2 photocatalyst for N2 fixation, bilayer TiO2/SiO2 opal composite membranes were prepared via coupling TiO2 films with SiO2 opal photonic crystal (PC) films, and their photocatalytic performance in nitrogen fixation was tested. It was shown that when the photonic band gap (PBG) of the SiO2 PCs matched with the UV-Vis absorption edge of TiO2, the photon localization effect of SiO2 PCs was maximized to promote the photon capture of TiO2, resulting in more photogenerated electron–hole pairs for N2 activation. The photon localization effect of SiO2 PCs is negatively correlated with the thickness of the TiO2 films in composite membranes. The nitrogen fixation activity of the TiO2/SiO2 opal composite membrane, with the thickness of TiO2 film being 700 nm, was found to be 42.6 μmol gcat−1 h−1, which was 68% higher than that of the plain TiO2 film.
研究领域:
材料科学
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化学工程
·
催化
·
光子学
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 14
·3590-3597
·
IF 7.779
Qiang Wang,Wen Song,Yang Lan,Liling Cao,Ling Huang,Daojiang Gao,Jian Bi,Guohong Zou
KBe2BO3F2 (KBBF) with a perfect honeycomb hexagonal layered structure is the sole practical deep-ultraviolet (DUV) nonlinear optical material which could generate DUV coherent light through direct frequency doubling. However, the layered growth habit and the toxicity of Be severely hinder its extensive applications. Herein, a non-centrosymmetric fluoride carbonate, KLi2CO3F, was successfully developed via chemical co-substitution with KBBF as the prototype. KLi2CO3F preserves the structural merits of KBBF, containing neatly arranged infinite planar [Li2CO3F2]∞ layers. In particular, compared with the weak interlayer K–F electrostatic attraction in KBBF, KLi2CO3F presents a stronger interlayer binding energy induced by the shorter and stronger Li–F bonds, which effectively overcomes the layered tendency of crystal growth. Simultaneously, KLi2CO3F exhibits a large birefringence of approximately 0.102@546 nm and a short ultraviolet absorption edge down to 190 nm, indicating that it is a promising DUV birefringent material.
研究领域:
材料科学
·
光学
·
晶体学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2023
·
IF 4.6
Ruixin Guo,Shu Guo,Mingjun Xia,Lijuan Liu,Minjuan Li,Sangen Zhao,Xiaoyang Wang
Ba1.09Pb0.91Be2(BO3)2F2 (BPBBF), a previously unreported lead-containing beryllium borate fluoride, has been successfully grown through a high-temperature flux method. Its structure is solved by single-crystal X-ray diffraction (SC-XRD), and it is optically characterized via infrared, Raman, UV–vis–IR transmission, and polarizing spectra as well. SC-XRD data suggests that it can be indexed by a trigonal unit cell (space group P3m1) with lattice parameters a = 4.7478(6) Å, c = 8.3856(12) Å, Z = 1, and V = 163.70(5) Å. This material could be considered as a derivative of the Sr2Be2B2O7 (SBBO) structural motif. It consists of 2D [Be3B3O6F3]∞ layers in the crystallographic ab plane, with divalent Ba2+ or Pb2+ cations serving as spacers among the adjacent layers. Ba and Pb were found to adopt a disordered arrangement in the trigonal prismatic coordination within the BPBBF structural lattice, which is evidenced by both structural refinements against SC-XRD data and energy dispersive spectroscopy. The UV absorption edge (279.1 nm) and birefringence (Δn = 0.054@ 546.1 nm) of BPBBF are confirmed by UV–vis–IR transmission and polarizing spectra, respectively. The discovery of this previous unreported SBBO-type material, BPBBF, along with other reported analogues such as BaMBe2(BO3)2F2 (M = Ca, Mg, and Cd), provide a prodigious example for tuning the bandgap, birefringence, and short UV absorption edge via simple chemical substitution.
研究领域:
材料科学
·
晶体学
·
光学材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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