DALTON TRANSACTIONS
·
2015
·Vol. 44
·期 39
·17286-17292
·
IF 4.197
Xia Xu,Zhuo Wang,Pengpeng Lei,Xiuling Liu,Yue Su,Lile Dong,Shuang Yao,Liang Zhou,Shuyan Song,Jing Feng,Hongjie Zhang
Cubic KLu3F10 nanocrystals have been fabricated by doping Mn2+ ions via a liquid–solid solution (LSS) hydrothermal method. With an increase in the Mn2+ level, a phase transformation from orthorhombic KLu2F7 to cubic KLu3F10 associated with evolution of the particle morphologies and sizes is evident. The phase transformation mechanism based on doping with Mn2+ ions was studied via a series of time-controlled experiments and the enhancement of the intensity of upconversion luminescence (UCL) via doping with Mn2+ ions is discussed in detail. In addition, under 980 nm excitation, the UCL properties of Er3+/Tm3+/Ho3+-doped KLu3F10:Yb3+ upconversion nanoparticles (UCNPs) have been investigated and a possible UCL mechanism has been discussed. It has been demonstrated that cubic KLu3F10 is an excellent host for upconversion luminescence.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2017
·Vol. 27
·期 28
·1701130
·
IF 12.124
Dunping Cao,Congling Yin,Dingren Shi,Zhengwen Fu,Jincang Zhang,Chilin Li
Exploring novel structure prototype and mineral phase, especially open framework material, is crucial to developing high-performance Na-ion battery cathodes in view of potentially faster intrinsic diffusion of Na + in lattices. Perovskite phases have been widely applied in solar cells, fuel cells, and electrocatalysis; however, they are rarely attempted as energy storage electrode materials. This study proposes pre-expanding perovskite iron fluoride (KFeF 3 ) framework by stuffing large-sized K + as a channel filler, which is advantageous over Na + , NH 4 + , and H 2 O molecule filler in terms of structure robustness, symmetry, and connectivity. K + stuffing leads to the preservation of a more “regular” cubic phase with fast isotropic 3D diffusion as a consequence of no distortion of FeF 6 octahedra during K-Na electrochemical exchange and following Na-insertion cycling. High-rate Na-storage is achievable with a reversible capacity of 110, 70, and 40 mAh g −1 at 0.1, 2, and 10 C, respectively, for this open framework fluoride cathode, benefiting from solid solution electrochemical behavior and high intrinsic diffusion coefficient. It is thought that this rate performance is currently the best among Na-storage fluoride materials.
研究领域:
材料科学
·
储能
·
电化学
·
无机化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Hao Liang,Weitong Lin,Qiming Wang,Wei Zhang,Shixue Guan,Jiawei Zhang,Ji-Jung Kai,Duanwei He,Fang Peng
Cubic boron nitride (cBN), a typical superhard material, has garnered significant interest for both fundamental scientific research and technical applications. Here, nanostructured cBN with high-density nanotwins and stacking faults was synthesized by rapid quenching using hexagonal boron nitride (hBN) as the starting material at a moderate temperature (2200 K) and low pressure (13 GPa). This synthetic nanostructured cBN exhibits high Vickers hardness (78 GPa), high fracture toughness (11.8 MPa·m 1/2 ), and extremely high oxidization temperature (1565 K). We propose that the refined grain structure and excellent mechanical properties of the cBN synthesized in this study is attributed mainly to dislocation slips and (111) mechanical nanotwins that dominate this phase transformation.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
Crystals
·
2025
·Vol. 15
·期 7
·622
·
IF 2.4
Haoyu Zhao,Junliang Zhu,Zhonghe Zhu,Lin Bo,Wenying Wang,Xingshuo Liu,Changcun Li,Degang Zhao
Cubic phase SnSe-based materials have great potential in the field of thermoelectricity due to their reduced carrier scattering, increased band degeneracy, and ultra-low lattice thermal conductivity. Nevertheless, systematic studies on the influence of element doping on the thermoelectric properties of cubic SnSe-based materials are still relatively scarce. To enrich the research in this field, this work investigates the effects of Ge doping on the phase composition, electrical and thermal transport properties of cubic Sn0.50Ag0.25Bi0.25Se0.50Te0.50thermoelectric materials. X-ray diffraction (XRD) analysis confirmed that the Ge-doped samples exhibited a single cubic phase structure, while scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) revealed a uniform distribution of elements within the samples. The results indicate that increasing the Ge doping content substantially enhances their electrical conductivity, albeit at the expense of elevated thermal conductivity. By optimizing the content of Ge-doping, the thermoelectric figure of merit (ZT) reached 0.74 at 750 K. Notably, while moderate Ge doping enhances electrical transport properties, excessive doping leads to a significant rise in thermal conductivity, ultimately constraining further thermoelectric performance gains.
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 40
·16530-16540
·
IF 3.5
Xuekai Wang,Yongze Cao,Xianglan Yan,Sai Xu,Jinsu Zhang,Tianshuo Liu,Baojiu Chen
Cubic and hexagonal structured SrTa4O11(STO):Er3+/Yb3+ phosphors were synthesized by a solid state reaction (SSR) and molten salt synthesis (MSS). The upconversion luminescence (UCL) intensity of these samples was investigated. Hexagonal STO:Er3+/Yb3+ with much or a little β-Ta2O5 can be synthesized by SSR in air or vacuum, respectively, and the UCL intensity of the sample synthesized by SSR in a vacuum is higher. Cubic STO:Er3+/Yb3+ can be synthesized by MSS with KCl flux, and hexagonal STO:Er3+/Yb3+ can be synthesized by MSS with B2O3 flux, which has the strongest UCL intensity among all the samples compared with samples prepared by SSR. The sample by MSS with B2O3 flux was acid pickled (AP) with HCl solution, and the green UCL intensity increased by 2.18 times, which reached 32.95% for β-NaYF4:Er3+/Yb3+. The UCL intensity of the hexagonal STO:Er3+/Yb3+ is much higher than that of the cubic structure, which is due to the layered structure and the non-central symmetry of the Er3+/Yb3+ doped sites in hexagonal STO:Er3+/Yb3+. The temperature sensitivity of samples is evaluated by luminescence intensity ratio (LIR) technology. The maximum relative sensitivity is 0.0099 K−1 at 303 K. All the results show that hexagonal STO:Er3+/Yb3+ has excellent pure green UCL intensity and high temperature sensitivity, which can be used in UCL display and temperature sensing.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2016
·
IF 3.782
Jin Han,Maowen Xu,Yubin Niu,Min Jia,Ting Liu,Chang Ming Li
A novel cubic KTi 2 (PO 4 ) 3 is successfully synthesized via a facile hydrothermal method combined with a subsequent annealing treatment and further used as electrode material for sodium-ion batteries for the first time. For comparison, carbon-coated KTi 2 (PO 4 ) 3 obtained by a normal cane sugar-assisted method reveals superior electrochemical performances in sodium-ion battery. Besides of the high coulombic efficiency of nearly 100% after 100 cycles, a stable capacity of 112 mA h g −1 can be achieved at 0.5 C after 100 cycles, and still maintains to 105 mA h g −1 after 500 cycles with capacity retention of approximately 90%.
研究领域:
材料科学
·
电化学
·
储能
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2019
·Vol. 48
·期 11
·3658-3663
·
IF 4.052
Naike Shi,Qilong Gao,Andrea Sanson,Qiang Li,Longlong Fan,Yang Ren,Luca Olivi,Jun Chen,Xianran Xing
Negative thermal expansion (NTE) behavior is an interesting physical phenomenon, but the number of NTE materials is limited. In this study, a new NTE compound has been found, FeFe(CN)6 Prussian blue analogue, where the average linear coefficient of thermal expansion (αl) is −4.260 × 10−6 K−1 between 100 and 450 K. The NTE properties and local vibration dynamics have been investigated by joint experiments of synchrotron X-ray diffraction, X-ray pair distribution function, and extended X-ray absorption fine structure spectroscopy. It has been observed that the Fe–C/Fe–N bonds expand with increasing temperature, while the unit cell shrinks in FeFe(CN)6. The vibration directions of both Fe–C and Fe–N prefer to be perpendicular to the linkage of Fe–CN–Fe rather than being parallel. More pieces of evidence indicate that the transverse vibrations of N atoms dominate the NTE behavior of FeFe(CN)6. The present results prove directly that the transverse thermal vibrations of C and N atoms are crucial for the occurrence of the NTE of Prussian blue analogues.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
·
2019
·
IF 5.162
Mingtao Yan,Huiyuan Geng,Peng Jiang,Xinhe Bao
Thermoelectric properties of orthorhombic or rhombohedral GeSe have attracted great attention recently, with the rise of its structural analog SnSe. However, the p -type cubic GeSe with higher symmetry and higher valence band degeneracy, which might exhibit higher thermoelectric performance, has never been synthesized. Here we report on the successful synthesis of p -type crystalline cubic GeSe by alloying with Sb 2 Te 3 and the spontaneously formed Ge-vacancies. An unexpected glass-like temperature independent lattice thermal conductivity is observed in crystalline cubic GeSe, which results from strong phonon scattering by vacancy-induced disorders. Combining the multiple scattering theory and chemical bond analysis, we further reveal the existence of Anderson localization induced by Ge-vacancies. The Anderson localization results in a nearly constant Seebeck coefficient with increasing the carrier concentration. These results provide a general insight towards understanding and improving the thermoelectric properties of thermoelectric materials with vacancies and atomic-scale disorders.
研究领域:
材料科学
·
凝聚态物理
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
He Yang,Andreas Goldbach,Wenjie Shen
Acetone hydrogenation is employed for investigating the structure sensitivity of H 2 activation over cobalt catalysts while the produced isopropanol garners increasing interest in the sustainable energy context e.g. as H 2 storage material and fuel for direct fuel cells. Both hexagonal close-packed (hcp) and face-centered cubic (fcc) Co can produce isopropanol with 100% selectivity below 150 °C with the reaction proceeding almost ten times faster over hcp Co. Hydrogenation rates are even higher over an hcp Co/Co 3 O 4 composite which remains highly selective to isopropanol despite that Co 3 O 4 yields mostly mesityl oxide and related products. The superior performance of hcp Co and its composite are attributed to efficient generation of atomic H on the metal and the presence of stronger sites for acetone activation on XRD-amorphous phases that are formed during reduction of the Co 3 O 4 precursor at 250 °C and 400 °C. These findings provide insight into the optimum structural design of highly active and selective low-temperature cobalt hydrogenation catalysts.
研究领域:
催化化学
·
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Minggang Zhang,Mingyang Lu,Haixi Pan,Haili Bai,Hui Mei,Laifei Cheng
Facet engineering is a surface optimization strategy to improve the physical and chemical properties of metal oxide semiconductors. To exploit a facile method to fabricate high-performance ethanol sensing material and study the sensing mechanism, a quasi-cubic α-Fe 2 O 3 was investigated, which with high-energy facets exposed. Cetyl trimethyl ammonium bromide (CTAB) surfactant was employed in the preparation of α-Fe 2 O 3 to control the shape and size. The resulting Fe 2 O 3 particles exhibited a mean size of 1.10 µm with high uniformity in size and shape. Additionally, the cubic structure can also optimize the electronic transmission path. Charge carriers are conducting between the cubes required to pass through the electron depletion layer on the surface, as the Fe 2 O 3 particles are separated. Thus, the resistance change of the electron depletion layer significantly affected the overall conductivity . The DFT calculation also confirmed that the exposed facets had high adsorption energy to ethanol molecules, which validated the experimental results. The resulting α-Fe 2 O 3 exhibited an excellent selectivity towards ethanol vapor with a response of 35.14–500 ppm ethanol gas, and the response and recovery times were 12 s and 41 s, respectively. Additionally, the sensing materials exhibited good long-term stability which maintained 92% of its initial response after 60 days, potential using in practical ethanol gas detection.
研究领域:
材料科学
·
化学工程
·
纳米技术
·
气体传感
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xinyu Ping,Bin Meng,Xiaohua Yu,Zhiyuan Ma,Xiaoyu Pan,Wu Lin
Cubic bixbyite-structured high-entropy oxides (HEOs) are regarded as potential candidates in high temperature thermal insulation field in recent years. However, their relevant properties are still needed to be explored for possible applications. In this work, twelve new high-entropy oxides (HEO1-12) of (5Re 0.2 ) 2 O 3 (Re represents five elements selected from Ce, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb) are prepared by solution combustion synthesis method combined with conventional sintering. Except HEO10 with a single monoclinic phase, other samples have a single bixbyite phase. The average grain size of bixbyite-structured samples is within 0.76 ∼ 4.96 μm. Then, the samples of HEO4, 5, 7–9 are chosen to study their mechanical and thermal properties. Their nano-modulus, nano-hardness, fracture toughness K IC , brittleness M and surface fracture energy are in the range of 152.42 ∼ 237.33 GPa, 9.22 ∼ 12.65 GPa, 1.77 ∼ 2.51 MPa·m 1/2 , 2.35 ∼ 3.09 μm −1/2 and 9.00 ∼ 22.49 J m −2 , respectively. HEO4, i.e., (Ce 0.2 Nd 0.2 Sm 0.2 Dy 0.2 Gd 0.2 ) 2 O 3 , exhibits higher K IC (1.92 MPa·m 1/2 ) and lower M (2.71 μm −1/2 ) than another reported cubic bixbyite-structured HEO of (Eu 0.2 Er 0.2 Lu 0.2 Y 0.2 Yb 0.2 ) 2 O 3 . Among the five samples, HEO4 has the lowest thermal conductivity κ (1.88 ∼ 2.55 W·m −1 ·K −1 in 25 ∼ 500 °C), which is much lower than bixbyite-structured Y 2 O 3 . In addition, HEO4 possesses a lower oxygen diffusion compared with 8YSZ in 600 ∼ 700 °C, which endows it the better oxygen barrier property. To sum up, HEO4 could be a promising candidate for high temperature thermal insulation applications due to its excellent comprehensive properties.
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DOI
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2014
·Vol. 29
·期 10
·1175-1182
·
IF 1.815
Wang Wenyan,He Yiming,Wu Tinghua,Wu Ying
SnZn(OH) 6 (ZHS) hollow cubes were synthesized by a facile self-templated method at room temperature, and Ag/AgCl/ZHS particles were prepared by a photodepositing method. The crystalline structure and morphology of the prepared particles were characterized by x-ray diffraction, UV-vis diffuse reflectance spectroscopy, scanning electron microscopy, and N 2 adsorption. The results indicated that the particles had almost uniform monoclinic geometry and size. The photocatalytic oxidation of Rhodamine B was used to evaluate the photocatalytic activity of the synthesized photocatalysts. It is found that the hollow Ag/AgCl/ZHS showed the highest catalytic performance under visible or UV light, which can be attributed to the synergetic effect of Ag, AgCl, and ZHS.
研究领域:
材料科学
·
光催化
·
纳米材料
·
环境化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）