JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Dan Yang,Qingfeng Guo,Libing Liao,Yidi Zhang,Lefu Mei,Haikun Liu
In this paper, K 3 ScF 6 :Er 3+ ,Yb 3+ up-conversion luminescent materials with cryolite structure were synthesized via solid-state method. The X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL) under the excitation of a 980 nm laser with different power density were used to investigate the phase structure, elemental composition , and up-conversion luminescence properties of K 3 ScF 6 :Er 3+ ,Yb 3+ . The quenching concentrations of Yb 3+ and Er 3+ were confirmed to 0.15 and 0.05 (mol concentration) in this system, respectively. Upon 980 nm excitation, the K 3 ScF 6 :Er 3+ ,Yb 3+ showed a typical transition of Er 3+ which contains two main bands in the visible region that green and red. According to the fitting result of the pump power dependence of up-conversion intensity, all the green and red up-conversion emission of K 3 ScF 6 :0.05Er 3+ ,0.15 Yb 3+ belong to the two-photon process. To better understand the origin of radiation and energy transfer mechanism of the red and green up-conversion, the possible mechanism and electron transition process were also discussed.
研究领域:
材料科学
·
无机化学
·
光功能材料
·
固体化学
·
发光物理
✓ 已验证
DOI
高影响因子
Sustainable Energy & Fuels
·
2020
·Vol. 4
·期 8
·3943-3950
·
IF 5.503
Hongpeng Zhou,Menglei Feng,Peiyuan Li,Xiangnan Gong,Dingke Zhang,Shijian Chen
Layered Sb2Se3 consists of infinite chains of repeating Sb4Se6 units stacked along the c-axis via Sb–Se covalent bonds, whereas they are linked by van der Waals force along the a-axis and b-axis. It usually tends to grow along the [hk0] orientation with low surface energy. However, [001]-oriented growth, which efficiently enhances charge transport, is often considered unstable due to its high surface energy. Herein, we propose a growth method to fabricate Sb2Se3 thin films with the preferential [001]-orientation on various substrates (Mo, MoSe2, SLG, NiO, SiO2 and FTO). This crystal facet design of preferentially [001]-oriented Sb2Se3 exposes the majority of the nanoribbons vertically aligned to the substrate, and thus maximally improves the charge transport, which may find applications in diverse optoelectronic devices. We confirmed their performance in photoelectrochemical water reduction. The preferentially [001]-oriented Sb2Se3 photocathode exhibited an impressive photocurrent density of −20.5 mA cm−2 at 0 V vs. RHE and a maximum photocurrent density of −28 mA cm−2 at −0.2 V vs. RHE under 1 sun AM 1.5 G illumination. Thus, the successful use of this [001]-Sb2Se3 photocathode paves the way for the development of high-efficiency Sb2Se3-based devices for optoelectronic applications.
研究领域:
材料科学
·
半导体物理
·
光电化学
·
纳米材料
·
能源材料
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2022
·Vol. 51
·期 45
·17328-17337
·
IF 4.569
Yan Zhu,Hongmei Qing,Wenbo Dong,Mingrong Dong,Tao Shen,Jian Cui
Copper zinc tin sulfide (Cu2ZnSnS4, CZTS) is attracting interest in photovoltaic applications due to its proper band gap, low cost and low toxicity. It has been found that two phases can be fabricated, i.e. kesterite and wurtzite CZTS structures. Though kesterite CZTS is proven to be thermodynamically stable, the free energy difference between kesterite and wurtzite CZTS is rather small. So, wurtzite CZTS can also stably exist under ambient conditions. Controlling the phase formation can expand the dimensions to optimize the performance of applications based on CZTS. In this study, we found that phase control can be achieved by simply using a mixed solvent of ethylene glycol and triethylenetetramine (TETA) in a two-stage heating process. It is found that the incorporation of the reductive solvent of TETA during the 1st heating process converts the phase of the precipitates from CuS (TETA poor) to Cu7S4 (TETA rich). In the subsequent 2nd heating stage, the phase of the final products is determined to be kesterite CZTS originating from CuS and wurtzite CZTS from Cu7S4, respectively. Thus, the key to control the phases of the final products is to control the chemical environment of Cu under Cu1+-rich or Cu2+-rich conditions in the fabrication process, which corresponds to the phase of the final products of wurtzite CZTS or kesterite CZTS, respectively. This summarized principle can not only be used to explain the previous versatile experimental results but also to guide the controlled synthesis of various phases of CZTS and CZTS-like materials in applications.
研究领域:
材料科学
·
无机化学
·
半导体材料
·
纳米科技
·
光伏材料
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2020
·
IF 3.204
Yun Zhang,Shihua Ding,Tianxiu Song,Yingchun Zhang
CoSnNb 2 O 8 ceramic with medium-permittivity was initially generated. Compositionally induced phase formation was identified by X-ray diffraction. Tetragonal rutile-type CoSnNb 2 O 8 was obtained from the reaction of SnO 2 with intermediate phase CoNb 2 O 6 . Both the dielectric constant ε r and quality factor Q × f initially increased with the sintering temperature, reaching the maxima at around 1225 °C, and declined thereafter. They were discussed based on the ionic polarizabilities and packing fraction, respectively. The temperature coefficient of resonant frequency τ f primarily depended on the Nb-site bond valence, as well as oxygen octahedra distortion. When sintered at 1225 °C, the CoSnNb 2 O 8 ceramic exhibited optimum properties with ε r = 31.8, Q × f = 43,000 GHz, and τ f = 35.01 ppm/°C.
研究领域:
材料科学
·
无机非金属材料
·
介电物理
·
功能陶瓷
·
微波材料
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Sai-Li Zheng,Yonghe He,Xiao-Kang Qiu,Yuan-Hui Zhong,Lai-Hon Chung,Wei-Ming Liao,Jun He
A novel metal-organic framework [CuCN(TMBP)·H 2 O] n ( TCuCN ) has been synthesized by the reaction of 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (TMBP) and CuCN. Its structure was determined by single-crystal X-ray diffraction (SCXRD) analysis and further characterized by power X-ray diffraction (PXRD) analysis, FT-IR spectroscopy and thermogravimetric (TG) analysis. Previously reported structurally analogous TCuCl , TCuBr , TCuI have also been synthesized for Br 2 adsorption comparison. All of these four MOFs exhibited reversible uptake of Br 2 vapor judging by the unchanged PXRD patterns . Among four MOFs, Br 2 -loaded TCuI showed the most uptake amount of Br 2 (15.7 wt%), providing the formula to be TCuI ·0.33Br 2 . The different uptake amount of Br 2 for TCuX (X = CN, Cl, Br, I) should be mainly ascribed to the intermolecular interaction between CuX and Br 2 .
研究领域:
无机化学
·
材料化学
·
配位化学
·
多孔材料
·
气体吸附
✓ 已验证
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2013
·Vol. 23
·期 6
·1492-1500
·
IF 1.174
Zhang Nan,Fan Yu-Hua,Bi Cai-Feng,Zhang Xia,Zhang Peng-Fei,Zhang Zhong-Yu,Li Xin
Three novel transition metal coordination polymers, [Ni(C 18 H 16 N 3 O 2 ) 2 ·2CH 3 OH]
n
( 1 ), [Zn(C 18 H 16 N 3 O 2 ) 2 ·4CH 3 OH]
n
( 2 ) and [Cd(C 18 H 16 N 3 O 2 ) 2 ·2CH 3 OH]
n
( 3 ) (C 18 H 16 N 3 O 2 =2-acetylpyridine- d -tryptophan) were synthesized and characterized by elemental analysis, IR, UV, 1 H NMR and X-ray diffraction single crystal analysis. The analyses of the structures indicate that all three materials crystallize in the tetragonal crystal system, space group P 4 1 2 1 2. They have similar structures; i.e., the Schiff base coordinates in its deprotonated form and behaves as a hexadentate (4N+2O) coordinated ligand to form a distorted octahedron geometry. On the other hand, as a result of the alternate arrangement of chains through N–H···O intermolecular hydrogen bonds interactions, 2-D layers are formed for the three complexes. Furthermore, the luminescent properties and thermal stabilities of the three complexes were investigated.
研究领域:
无机化学
·
配位化学
·
材料化学
·
晶体工程
·
光物理化学
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2018
·
IF 2.687
Xue Chen,Ning Li,Yuan Li,Ping Che
In this work the CH 3 NH 3 PbI x Cl 3−x perovskite is obtained by applying vacuum-rotary evaporation procedure with a precursor solution of PbCl 2 and CH 3 NH 3 I in dimethylformamide. Thermal gravimetric and differential thermal analysis (TG-DTA) and the variable temperature powder X-ray diffraction ( in situ XRD) are employed to research the effect of thermal treatment on the decomposition and the crystal structure of perovskite . It is found that tetragonal to cubic phase transition in the typical perovskite disappears in mixed perovskite crystals because the stabilizing action of Cl. The excess Cl in the precursor leads to the intermediate structure CH 3 NH 3 PbCl 3 , and then transforms into CH 3 NH 3 PbI 3 with temperature increasing.
研究领域:
材料科学
·
无机化学
·
固体物理
·
能源材料
·
晶体学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Li Fang,Liang Li,Zan Qu,Haomiao Xu,Jianfang Xu,Naiqiang Yan
A novel method was developed and applied for the treatment of simulated wastewater containing multiple heavy metals. A sorbent of ZnS nanocrystals (NCs) was synthesized and showed extraordinary performance for the removal of Hg 2+ , Cu 2+ , Pb 2+ and Cd 2+ . The removal efficiencies of Hg 2+ , Cu 2+ , Pb 2+ and Cd 2+ were 99.9%, 99.9%, 90.8% and 66.3%, respectively. Meanwhile, it was determined that solubility product ( K sp ) of heavy metal sulfides was closely related to adsorption selectivity of various heavy metals on the sorbent. The removal efficiency of Hg 2+ was higher than that of Cd 2+ , while the K sp of HgS was lower than that of CdS. It indicated that preferential adsorption of heavy metals occurred when the K sp of the heavy metal sulfide was lower. In addition, the differences in the K sp of heavy metal sulfides allowed for the exchange of heavy metals, indicating the potential application for the sequential removal and separation of heavy metals from wastewater. According to the cumulative adsorption experimental results, multiple heavy metals were sequentially adsorbed and separated from the simulated wastewater in the order of the K sp of their sulfides. This method holds the promise of sequentially removing and separating multiple heavy metals from wastewater.
研究领域:
环境科学
·
环境工程
·
纳米材料
·
水污染控制
·
化学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 50
·期 1
·1452-1460
·
IF 5.2
Shangwei Wang,Ran Pang,Xuexia Chen,Tao Tan,Qi Wang,Chengyu Li,Su Zhang,Taixing Tan,Hongpeng You,Hongjie Zhang
Near-infrared phosphor conversion light-emitting diode (NIR pc-LED) is a widely used ideal NIR light source due to its unique advantages of low cost, energy saving, compactness and long operational lifetime. However, there is currently a scarcity of appropriate phosphor for NIR light sources utilized in spectral detection, with emission peak larger than 850 nm and steady spectrum output of ultra broadband spectra. Here, a broadband Cr 3+ activated LiScSnO 4 (LSS) phosphor ( λ ex-max = 460 nm) matching the pump band of commercial blue LED chips has been developed, which shows a long wavelength NIR emission peaking at 900 nm. Cr 3+ simultaneously replace the Wyckoff site co-occupied by Sc and Sn in LSS. Due to the difference of local environment of the specific crystal field , two different wide emission bands are caused. These two broad emission bands both contribute to the broadband luminescence with a full width at half maximum (FWHM) of 227 nm. Benefiting from the crystallography consistent Wyckoff position occupation of Cr 3+ ions, the spectral distribution of LSS:Cr 3+ exhibit excellent stability over a wide temperature span (80–423 K). The broadband NIR pc-LED prototype based on LSS:Cr 3+ shows great potential in NIR spectrum detection, night vision imaging applications.
研究领域:
材料科学
·
光学工程
·
固态物理
·
光电子学
·
分析化学
✓ 已验证
DOI
高影响因子
Advanced Science
·
2019
·Vol. 6
·期 13
·1900462
·
IF 15.804
Chenghao Bi,Shixun Wang,Stephen V. Kershaw,Kaibo Zheng,Tönu Pullerits,Sergey Gaponenko,Jianjun Tian,Andrey L. Rogach
Colloidal all-inorganic perovskite nanocrystals have gained significant attention as a promising material for both fundamental and applied research due to their excellent emission properties. However, reported photoluminescence quantum yields (PL QYs) of blue-emitting perovskite nanocrystals are rather low, mostly due to the fact that the high energy excitons for such wide bandgap materials are easily captured by interband traps, and then decay nonradiatively. In this work, it is demonstrated how to tackle this issue, performing self-assembly of 2D perovskite nanoplatelets into larger size (≈50 nm × 50 nm × 20 nm) cuboid crystals. In these structures, 2D nanoplatelets being isolated from each other within the cuboidal scaffold by organic ligands constitute multiple quantum wells, where exciton localization on potential disorder sites helps them to bypass nonradiative channels present in other platelets. As a result, the cuboid crystals show an extremely high PL QY of 91% of the emission band centered at 480 nm. Moreover, using the same synthetic method, mixed-anion CsPb(Br/Cl) 3 cuboid crystals with blue emission peaks ranging from 452 to 470 nm, and still high PL QYs in the range of 72–83% are produced.
研究领域:
材料科学
·
纳米科技
·
光电子学
·
半导体物理
·
胶体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2012
·
IF 2.159
Mi Wang,Yanfeng Gao,Lei Dai,Chuanxiang Cao,Xuhong Guo
Nanoscaled SnO 2 with different morphologies has been synthesized via a simple hydrothermal process at 180 °C using polyvinylpyrrolidone (PVP), sodium dodecyl sulfonate (SDS), cetyl trimethyl ammonium bromide (CTAB) or tetrapropyl ammonium bromide (TPAB) as surfactant . All the prepared SnO 2 are of a tetragonal crystal structure. Nanocubes, nanorods , nanosheets , nanobelts and nanoparticles were prepared when changing the type and dosage of organic surfactants. It is shown that anionic surfactant (SDS) and cationic surfactant (CTAB or TPAB) at their suitable addition amounts can largely influence the morphologies of SnO 2 nanocrystals . The effect is significantly dependent on the solvent types: water or ethanol. The non-ionic surfactant (PVP) can also change the morphologies like SDS but the impacts are less obvious. The effect of surfactants on the shape and size of SnO 2 nanoparticles was discussed in detail. The particle growth mechanism is described based on the electrostatic interactions and Van der Waals’ forces.
研究领域:
材料科学
·
纳米技术
·
无机化学
·
物理化学
✓ 已验证
DOI
高影响因子
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES
·
2017
·
IF 3.756
Yu Huang,Jin-Mei Li,Zhi-Hui Lai,Jun Wu,Tong-Bu Lu,Jia-Mei Chen
Both cocrystal and nanocrystal technologies have been widely used in the pharmaceutical development for poorly soluble drugs. However, the synergistic effects due to the integration of these two technologies have not been well investigated. The aim of this study is to develop a nano-sized cocrystal of phenazopyridine (PAP) with phthalimide (PI) to enhance the release rate and oral bioavailability of PAP. A PAP–PI nano-cocrystal with particle diameter of 21.4 ± 0.1 nm was successfully prepared via a sonochemical approach and characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and dynamic light scattering (DLS) analysis. An in vitro release study revealed a significant release rate enhancement for PAP–PI nano-cocrystal as compared to PAP–PI cocrystal and PAP hydrochloride salt. Further, a comparative oral bioavailability study in rats indicated significant improvement in C max and oral bioavailability (AUC 0 − ∞ ) by 1.39- and 2.44-fold, respectively. This study demonstrated that this novel nano-cocrystal technology can be a new promising option to improve release rate and absorption of poorly soluble compounds in the pharmaceutical industry.
研究领域:
药剂学
·
药物递送
·
纳米医学
·
药物代谢
·
晶体工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）