CRYSTAL GROWTH & DESIGN
·
2022
·
IF 4.01
Zeyu Cheng,Hao Ren,Yazhao Wang,Shengdi Ta,Peng Zhang,Yuhua Yang,Shoulei Xu,Bernard Albert Goodman,Wen Deng
Large-size and high-quality stable ZrO2 single crystals containing x mol % Yb2O3 (x = 7, 8, 9, 10) (denoted as xYbSZ), and 8YbSZ crystals doped with 0.5 mol % Er2O3 were grown by the optical floating zone (OFZ) method. Yb3+ was indicated by XRD and Raman spectroscopy to have successfully entered into the ZrO2 lattice, which was stabilized in the cubic phase when the concentration of Yb2O3 was ≥8 mol %. Er3+ successfully entered the 8YbSZ lattice, and its spectral absorption intensity was enhanced compared to Er3+ in the corresponding yttria-stabilized zirconia (8YSZ), thus demonstrating that the Yb3+ ion has an excellent sensitizing effect on the up-conversion luminescence of Er3+. Fluorescence decay curves show that the up-conversion luminescence excited state lifetime of Er3+ is significantly enhanced in 8YbSZ compared to 8YSZ. Thus, these results demonstrate that Yb3+ ions not only successfully stabilize ZrO2 in the cubic phase structure but also maintain their role as an up-conversion luminescence sensitizer for Er3+ ions.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Chu Cheng,Jie Zou,Yucun Zhou,Zi Wang,Han Jin,Guangzhong Xie,Jiawen Jian
A mixed potential type alcohols gas sensor based on an yttrium stabilized zirconia (YSZ) electrolyte and an La 0.8 Sr 0.2 MnO 3 (LSM) sensing electrode was fabricated. The influences of YSZ-LSM interface on sensing performance were studied by multiple methods including X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis and differential scanning calorimetry (TG-DSC) and electrochemical impendence spectroscopy (EIS). The sensor with 1150 °C-sintered interface showed an ultralow detection limit of 50 ppb alcohols (methanol and ethanol) at 500 °C in air. The response voltage was independent of water, CO, CO 2 and NO x . The sensor exhibited a reasonable selectivity towards alcohols under the existence of several kinds of volatile organic compounds. Meanwhile, the sensor showed a good repeatability and a suitable long-term stability. Based on the polarization curves and EIS results, a mixed potential mechanism was proposed. These results demonstrate the promising potential of using the LSM-based sensor for human exhale test.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Advanced Materials Interfaces
·
2020
·Vol. 8
·期 1
·2001606
·
IF 4.948
Zuohao Wen,Yujie Ke,Chengchen Feng,Shuliang Fang,Miuyang Sun,Xinghai Liu,Yi Long
The VO 2 -based smart windows can dynamically and reversibly adjust the indoor solar irradiation to reduce the energy consumption for building glasses. This paper reports the first successful preparation of Mg-doped VO 2 @ZrO 2 core−shell nanocrystals with promoted thermochromic performance as well as tunable appearance and wettability. The achieved combination of T lum of 52.4% and ∆ T sol of 7.1% is comparable to the best-reported results of VO 2 -based core−shell rod structures. The thickness of ZrO 2 shell is tunable between 3 and 14 nm, resulting in a slightly hydrophobic surface and a slight color change toward blue-green and brighter produced films. The preparation method based on hydrothermal and UV-curing methods is facile. This work may inspire future development of VO 2 synthesis, their structure−property, and the application the thermochromic films for energy-saving purposes in buildings or automobiles.
研究领域:
材料科学
·
能源技术
·
纳米技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Lin-Lin Zhu,Hong-Lan Liu,Hua-Tay Lin,Xing-Hao Tan,Jia-Hao Chen,Xin Xu,Guang-Xiang Zhang,Yu-Jian Jian,Min-Min Dai,Cheng-Cai Zhao
Erbium oxide (Er 2 O 3 ) transparent ceramics were successfully fabricated with different contents of zirconia (ZrO 2 ) additive sintered at 1850 °C for 8 h in vacuum. The effects of ZrO 2 concentration on microstructure, optical, mechanical, and thermal properties of Er 2 O 3 transparent ceramics were systematically investigated in this study. With the concentration of ZrO 2 increasing from 0 to 4 at.%, the average grain size of Er 2 O 3 transparent ceramics decreased from 166.6 to 4.7 μm. Also, the Vickers hardness and fracture toughness were increased from 7.6 ± 0.3 to 10.1 ± 0.3 GPa and 0.69 ± 0.05 to 1.09 ± 0.03 MPa m 1/2 , respectively. However, the thermal diffusion coefficient and thermal conductivity reduced slightly after the doping of ZrO 2 . The in-line transmittance of 4 at.% ZrO 2 -doped Er 2 O 3 ceramics with the excellent optical quality reached 77% in the visible range and 78% at 1100 nm, which were 95% and 96% of the theoretical in-line transmittance of Er 2 O 3 single crystal, respectively. There were absorption peaks at 1500 nm and in the visible light range of 4 at.% ZrO 2 -doped Er 2 O 3 ceramics. The Er 2 O 3 ceramics developed in this study can be potential candidates for application in solid-state lasers.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2013
·Vol. 110
·期 2
·437-448
·
IF 1.104
Cui Wenjing,Jia Meilin,Ao Wulan,Zhaorigetu Bao
Nano-gold catalysts were prepared by the liquid reduction method and employed in the oxidative esterification of alcohols under ambient conditions. The effects of the supports and gold loading on the catalytic behavior were investigated. The catalysts were characterized by transmission electron microspectroscopy, X-ray diffraction, X-ray photoelectron microspectroscopy and atomic absorption spectrometry. The results indicated that nano-scale metallic state gold was highly dispersed on the support. 95 % methyl benzoate yield was obtained over 3 wt% Au/ZrO 2 catalyst at 30 °C under air atmosphere. Under optimized reaction conditions, benzyl alcohols with electron-withdrawing groups could give high selectivity to the corresponding methyl ester at moderate conversion of alcohols. However, when a benzyl alcohol with electron-donating group was used, high conversion of alcohol but low selectivity of the corresponding methyl ester was obtained. Low yields were obtained with aliphatic alcohols as substrates even at high temperature. The kinetic analysis of the oxidation from benzyl alcohol to benzaldehyde and from benzaldehyde to methyl benzoate was also described. The facile and simple procedure was a great option for direct synthesis of methyl esters from alcohols.
研究领域:
催化化学
·
材料科学
·
有机合成
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2016
·Vol. 9
·期 10
·795
·
IF 2.728
Jinzhu Tang,Qi Ding,Songwei Zhang,Guizhi Wu,Litian Hu
Nanomaterials, such as Graphene, h-BN nanoparticles and MoS2nanotubes, have shown their ability in improving the tribological performance of amorphous carbon (a-C) coatings. In the current study, the effectiveness of ZrO2nanoparticles (ZrO2-NPs) in lubricating the self-mated nonhydrogenated a-C contacts was investigated in boundary lubrication regime. The results showed that 13% less friction and 50% less wear compared to the base oil were achieved by employing ZrO2-NPs in the base oil in self-mated a-C contacts. Via analyzing the ZrO2-NPs and the worn a-C surface after tests, it was found that the improved lubrication by ZrO2-NPs was based on “polishing effects”, which is a new phenomenon observed between a-C and nanoparticles. Under the “polishing effect”, micro-plateaus with extremely smooth surface and uniform height were produced on the analyzed a-C surface. The resulting topography of the a-C coating is suitable for ZrO2-NPs to act as nano-bearings between rubbing surfaces. Especially, the ZrO2-NPs exhibited excellent mechanical and chemical stability, even under the severe service condition, suggesting that the combination of nonhydrogenated a-C coating with ZrO2-NPs is an effective, long lasting and environment-friendly lubrication solution.Keywords:amorphous carbon coating;ZrO2nanoparticles;friction coefficient;wear;polishing effect
研究领域:
材料科学
·
摩擦学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2016
·
IF 2.647
Lei Chen,Yujin Wang,Jia-Hu Ouyang,Xiaoming Duan,Yu Zhou
A novel pressure-assisted transient viscous phase sintering process has been used to fabricate dense BN-ZrO 2 -SiC composites at relatively low sintering temperatures . The sintering behavior and densification mechanism of BN-ZrO 2 -SiC composites incorporated with B 2 O 3 as transient viscous phase have been investigated. A rapid densification process occurs at about 1300 °C, which is attributed to the in-situ formation of SiO 2 by chemical reactions among ZrO 2 , SiC and B 2 O 3 . BN-ZrO 2 -SiC composites sintered at 1300 °C under 100 MPa exhibit a relative density of 95.9%, a flexural strength of 242 MPa and a fracture toughness of 4.1 MPa m 1/2 .
研究领域:
材料科学
·
工程学
✓ 已验证
产品关联
DOI
高影响因子
Coatings
·
2021
·Vol. 11
·期 7
·816
·
IF 2.881
Ziang Xu,Guiying Xu,Beibei Han,Kun Wang,Hui Ge,Baigang An,Dongying Ju,Maorong Chai,Lixiang Li,Weimin Zhou
To provide an effective method of green aquaculture, the photocatalysts of CuO/ZrO2/CB/coal-tar-pitch-SAC, which have visible light sterilization capacity, were successfully fabricated by coating ZrO2and CuO on the surface of CB/coal-tar-pitch-SAC. The structures of synthesized CuO/ZrO2/CB/coal-tar-pitch-SAC were investigated by XRD, XPS and SEM measurements in detail. It was observed that CuO/ZrO2/CB/coal-tar-pitch-SAC materials possess obvious heterojunction structure and excellent visible light sterilization capacity when the prepared weight ratio of CuO, ZrO2and CB/coal-tar-pitch-SAC is controlled as 0.03:0.3:1. Our studies can provide a beneficial reference for the design of photocatalysts with sterilization capacity in visible light.Keywords:photocatalyst;heterojunction;coal tar pitch;green aquaculture;ZrO2
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Express
·
2020
·Vol. 10
·期 6
·928-933
·
IF 1.65
Tian Liang,Hou Qinglin,Wang Yingxia,Hou Yihui
Si3N4 ceramic has excellent properties such as high temperature resistance, high hardness, and high thermal stability, but it has the disadvantages of high hardness and brittleness and difficulty in later processing. In this paper, ZrO2 was used as toughening
phase, and ZrO2 toughened Si3N4 ceramics was prepared by injection molding. The effects of ZrO2 sintering temperature and content on the mechanical properties and fracture morphology were studied. Experiments show that when the ZrO2 content
is 10 wt.% and the sintering temperature reaches 1650 °C, the bending strength and fracture toughness of Si3N4 ceramics reach the maximum at the same time, which are 767 MPa and 8.7 MPa·m1/2, respectively. The density is high. XRD analysis revealed
that if the sintering temperature is too high, the ZrO2/Si3N4 system will generate a large number of ZrN impurity phases that cannot be phase-transformed, which ultimately affects the ceramic properties. According to fracture morphology, the toughening mechanism
of ZrO2 is stress-induced phase transition.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 12
·7140-7149
·
IF 3.108
Yuchao Xu,Zongzhang Liu,Zheng Han,Minhua Zhang
ZnO promoted ZrO2–SiO2 catalysts synthesized by a sol–gel method were investigated in the two-step ethanol transforming to 1,3-butadiene process. The influence of promoters and the preparation method of the catalysts on the catalytic performance were studied in detail and the reaction conditions were optimized. The as-prepared catalysts were characterized by BET, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Resonance (FT-IR), X-ray photoelectron spectroscopy (XPS), FT-IR spectroscopy of adsorbed pyridine (Py-IR) and temperature-programmed desorption of NH3 (NH3-TPD). ZnO added ZrO2–SiO2 catalysts show the best catalytic activity and the catalysts prepared by the hybrid sol–gel method were superior to those prepared by the sol–gel coupled with impregnation method. The addition of promoters in the ZrO2–SiO2 system decreased the total acidity and lowered the selectivity to dehydration products. The best performance with ethanol/acetaldehyde conversion of 40.7% and 1,3-butadiene selectivity of 83.3% was reached at 310 °C, ethanol/acetaldehyde mole ratio of 3.5 and WHSV of 1.4 h−1 using a 0.5 wt% ZnO doped ZrO2–SiO2 catalyst.
研究领域:
催化化学
·
材料科学
·
能源化工
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2019
·
IF 0
Yumeng Zhou,Lijing Zhang,Shengyang Tao
Balancing the large surface area and high crystallinity of heterogeneous metal oxide catalysts is quite tricky. They are usually needed together to get both a large amount of active catalytic sites and high thermal stability. In this paper, the preparation of porous sulfate ZrO2 as solid acid catalysts is reported. The monolithic porous SiO2 created confined spaces in which porous ZrO2 was synthesized in it. The ZrO2 has excellent porous structure in which the specific surface area reaches 277 m2 g–1 and has good crystallinity. At the same time, they have high acid site loading (2.57 mmol g–1) upon sulfation. The sulfonic ZrO2 exhibits excellent catalytic performance when considering the dehydration of 5-HMF from d-fructose. The yield of 5-HMF is 87% for 60 min at 120 °C. Thus, this solid acid catalyst was a potential candidate for heterogeneous catalysis and biomass quick conversion.
研究领域:
催化化学
·
材料科学
·
可再生能源
✓ 已验证
产品关联
DOI
Molecular Catalysis
·
2024
·
IF 3.9
Yuhao Tian,Yixuan Li,Dong Cao,Qiying Liu,Weijie Cai
Photo-assisted ethanol dry reforming (EDR) for syngas production was deeply studied over nanorod-like Ni/ZrO 2 catalyst synthesized by precipitation and impregnation technique, respectively. The effect of light irradiation as well as catalyst preparation method on EDR reaction was investigated in detail with the stoichiometric feed ratios, over a temperature region of 350 to 550 °C. Photo-enhancement factor of ethanol conversion greatly increased from 10% (dark) to 40% (light) together with less formation of byproducts. Moreover, the experimental results depicted the better performance of P-Ni/ZrO 2 catalyst due to its abundant oxygen vacancies and strong Ni-Zr interaction. Enriched interfacial oxygen defects and more light-excited electrons facilitated the activation/dissociation of ethanol and CO 2 , thereby enhancing the catalytic activity. In addition, the mean particle size of NiO in P-Ni/ZrO 2 was (10.3 nm) which was smaller than that of the I-Ni/ZrO 2 (16.5 nm), suggesting its higher dispersion of active metal. The calculated apparent activation energy of P-Ni/ZrO 2 was 20.6 eV which was much less than the value of I-Ni/ZrO 2 (37.7 eV). This work might provide the valuable insight for the development of highly-efficient photothermal catalyst to enhance the value-added utilization of greenhouse gas CO 2 .
研究领域:
催化化学
·
能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）