NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 15
·7202-7211
·
IF 3.925
Zijing Wang,Shixiang Lu,Wenguo Xu,Ziwen Wang,Hao Zuo
Stable electrode materials with suitable electrochemical performance and high specific power are essential for the application of supercapacitors. A combination of La2O3, Co3O4, and graphene on nickel foam (LCGN) was prepared by hydrothermal synthesis and heat treatment to construct a three-dimensional flower-like structure. The synergistic effect between La2O3, Co3O4, and graphene dramatically improves the electrode stability. Owing to the special three-dimensional flower-like structure that improves ion diffusion and prevents structural collapse during charging and discharging, the prepared LCGN composite exhibits an excellent specific capacitance of 2945.11 F g−1 (2.95 F cm−2) at a current density of 1 A g−1 and excellent rate retention of 79.20% at 30 A g−1. Moreover, the LCGN//LCGN symmetric supercapacitor shows excellent performance with a specific capacitance of 403.92 F g−1 at 1 A g−1, with power density and energy density (12 000 W kg−1 at 53.9 W h kg−1), reflecting its industrial potential. Under the condition of 10 A g−1 current density, the capacitance retention rate is still extremely high, 89.3% after 30 000 continuous charge and discharge cycles, which certifies the promising potential of LCGN for high-performance energy storage devices.
研究领域:
材料科学
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电化学
·
能源存储
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产品关联
DOI
高影响因子
E-POLYMERS
·
2016
·Vol. 17
·期 3
·243-248
·
IF 0.812
Weidong Han,Bin Ding,Mira Park,Fuhai Cui,Su-Hyeong Chae,Hak-Yong Kim
Poly(vinyl pyrrolidone) (PVP)/La 3+ /Zr 4+ precursor nanofibrous membranes (LZPNM) with various Zr contents were synthesized via a simple electrospinning method. By controlling the Zr incorporation, the tensile properties of precursor membranes dramatically change from 0.77 to 1.73 MPa. Meanwhile, the average diameters of precursor nanofibers increase with the increase of Zr contents (from 283 to 535 nm). In addition, flexible La 2 O 3 -ZrO 2 nanofibrous membranes (LZNM) were obtained by calcination of corresponding precursor membranes. Furthermore, the structures and morphologies of the precursor membranes were investigated using X-ray powder diffraction analysis (XRD) and field-emission scanning electron microscopy (FE-SEM). The surface functional groups and thermal properties of the precursor membranes were measured via Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA).
研究领域:
材料科学
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纳米技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2017
·
IF 4.233
Yan Gao,Yiwei Zhang,Yuming Zhou,Chao Zhang,Hongxing Zhang,Shuo Zhao,Jiasheng Fang,Mengqiu Huang,Xiaoli Sheng
In this work, we report a feasible approach to synthesize a ternary nanocomposites , Pt/lanthanum doped mesoporous zirconium oxide (Pt/La 2 O 3 -ZrO 2 ), via an effective two-step method. Ordered mesoporous La 2 O 3 -ZrO 2 composites were firstly fabricated with mesoporous silica KIT-6 as a hard template. Subsequently, uniform Pt nanoparticles encapsulated by 4 hydroxyl-terminated poly (amidoamine) (G4-OH PAMAM) dendrimers were deposited on the La 2 O 3 -ZrO 2 composites. The as-prepared samples were characterized by transmission electron microscope (TEM), N 2 adsorption–desorption isotherm analysis, energy dispersion X-ray analysis (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and temperature programmed reduction (H 2 -TPR). The average size of PtDENs was found to be 1.48 nm in diameter. Furthermore, the introduction of La could improve the structure of the supports which was confirmed by XRD and H 2 -TPR analysis. The reduction of p-nitrophenol to p-aminophenol by NaBH 4 was utilized to evaluate the catalytic performances of catalysts. Results indicated that the Pt/La 2 O 3 -ZrO 2 catalyst calcined in nitrogen at 550 °C exhibited the highest catalytic performance and still kept the high catalytic activity even after six cycles. This phenomenon suggests that synergistic effect among Pt-Zr-La could enhance the catalytic efficiency. Finally, reaction mechanism was proposed for the reduction of p-nitrophenol.
研究领域:
材料科学
·
催化
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 107
·期 2
·704-718
·
IF 3.9
Jian Bao,Wei Du,Haitao Wu,Zhenxing Yue
In this study, two novel microwave dielectric ceramics were designed and synthesized using the solid-state reaction method based on the CaO–MoO 3 –La 2 O 3 pseudo-ternary phase diagram. The X-ray diffraction (XRD) patterns and Rietveld refinement results indicate that pure phase microwave dielectric ceramics (CaLa 2 (MoO 4 ) 4 and Ca 3 MoO 6 ) can be produced with CaO, MoO 3 , La 2 O 3 ratios of 1, 1, 4, and 3, 1, 0, respectively. CaLa 2 (MoO 4 ) 4 shows the potential value for application in Low Temperature Co-fired Ceramic technology. In addition, the Phillips–van Vechten–Levine theory, infrared reflectance spectrum, and THz time-domain spectrum are used further to study the structure-property relationship of the two ceramics. Finally, a 5G patch antenna used in Sub-6 GHz communication technology was successfully designed and manufactured. The study of the relationship between chemical bonds and dielectric properties of the two ceramics, along with the development of the patch antenna, establishes a foundation for scientific research and practical applications in related ceramic systems.
研究领域:
材料科学
·
陶瓷
·
电磁工程
·
电信
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DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
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2020
·
IF 2.485
Yi-Chuan Liu,Ya-Lan Liu,Yuan Zhao,Zhe Liu,Tong Zhou,Qing Zou,Xian Zeng,Yu-Ke Zhong,Mei Li,Zhong-xuan Sun,Wei-Qun Shi
For UO 2 -based spent fuel , it is usually electrochemically reduced and then refined in molten salt with respect to the so-called pyrochemical reprocessing approach. In this work, we report a new method with the assistance of NH 4 Cl to directly achieve convenient separation of UO 2 over La 2 O 3 in Ar atmosphere which does not require an electrochemical process . According to the results from both powder and pellet samples, the separation is achieved by dissolving La 2 O 3 into the LiCl–KCl molten salt with NH 4 Cl, whilst UO 2 cannot be dissolved and remains in solid form. It was found that the dissolution kinetics of La 2 O 3 in the powder sample was fast and its removal efficiency in the mixture of La 2 O 3 and UO 2 was high, but a specific amount of UO 2 was also dissolved, which lead to a low recovery efficiency of UO 2 . In contrast, when the pellet samples after sintering at 1473 K were used, the recovery efficiency of UO 2 can be increased. Nevertheless, the dissolution kinetics of La 2 O 3 was correspondingly reduced, and more NH 4 Cl was required to complete the dissolution reaction . By improving and optimizing the experimental conditions, the UO 2 recovery efficiency of 92.0% can be achieved, while the removal efficiency of La 2 O 3 was 94.4%. More importantly, this novel separation method may be also useful for the separation of UO 2 over mixed lanthanide oxides.
研究领域:
核化学与化工
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Gang Qu,Jingkai Zhou,Dandan Huang
The phase relationships of the ternary system Eu 2 O 3 - La 2 O 3 - ZrO 2 and binary Eu 2 O 3 - La 2 O 3 subsystem were experimentally and thermodynamically studied. Six three-phase fields and nine two-phase ones in the Eu 2 O 3 - La 2 O 3 - ZrO 2 system were investigated by X-ray diffraction, scanning electron microscopy and electron probe microanalysis with wavelength dispersive spectrometer at 1873 K and 1673 K. Nevertheless, there only existed a two-phase region in the Eu 2 O 3 - La 2 O 3 system in the temperature range from 1873 K to 1673 K. After that, the ternary mixing parameters for the system Eu 2 O 3 - La 2 O 3 - ZrO 2 including the binary interaction parameters in the Eu 2 O 3 - La 2 O 3 subsystem are optimized with the CALPHAD (CALculation of PHAse Diagrams) method, based on obtained experimental results. The high-temperature phase relationships and the special type of continuous solid solutions (La 2-x Eu x Zr 2 O 7 ) investigated in present work will contribute to exploring new materials with specific properties such as optical transparency.
研究领域:
材料科学
·
热力学
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产品关联
DOI
高影响因子
IRONMAKING & STEELMAKING
·
2024
·
IF 1.7
Jinming Wang,Xiangjun Liu,Wentao Guo,Zengwu Zhao,Zuolin Sun
The rare earth in the rare earth slag can be separated and enriched by heating and melting the rare earth slag and then slowly cooling crystallisation. In this process, it is of great significance to study the effect of chemical composition on the crystallisation of rare earth phase in slag and the effect of slag viscosity on crystal growth. The rare earth slag melt samples were prepared according to the main chemical composition of rare earth slag by using an analytical pure reagent. The effects of CaF2 and La2O3 contents on the phase structure and morphology of rare earth phase in CaO–SiO2–La2O3–CaF2 slags were studied by SEM-EDS and XRD. The relationship between the viscosity of the slag and the crystal growth behaviour was studied by measuring the melt viscosity with the cylinder rotation method. The results show that the rare earth in CaO–SiO2–La2O3–CaF2 slags exists in the form of CaLa4(SiO4)3O. The change of CaF2 and La2O3 content has no effect on the structure of rare earth phase, but the size of rare earth crystal phase changes obviously. With the increase of CaF2 and La2O3 content, the size of rare earth crystal phase increases gradually. CaF2 and La2O3 can reduce the viscosity transition temperature of slag melt and increase the crystallisation temperature range of rare earth phase to promote crystal growth.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Fazle Subhan,Sobia Aslam,Zifeng Yan,Ayaz Ahmad,U.J. Etim,Muhammad Naeem,Liu Zhen,Muhammad Ikram,Muhammad Yaseen
Lanthanum based adsorbents are promising in adsorptive desulfurization due to high activity. The dispersion degree of La 2 O 3 impacts desulfurization performance directly, and the development of an efficient strategy for La 2 O 3 dispersion still remained challenge. Herein, for the first time confined spaces and silanols of as-synthesized SBA-15 were used for dispersion of La 2 O 3 over mesoporous silica. The La(NO 3 ) 3 precursor is directly introduced into the confined spaces between silica walls and template of as-synthesized SAB-15 by solid state dispersion (SSD) strategy. The SSD strategy assists the formation of small sized La 2 O 3 with excellent dispersion after La precursor decomposition by the combined action of confined spaces and silanols. We also demonstrated that up to 20 wt% La 2 O 3 can be highly dispersed over as-synthesized SBA-15 (LaAS-20). Our investigations show that well-dispersion of La 2 O 3 correspond to high desulfurization activity for fuels, and the amount of thiophene captured can reach 0.12 mmol of S/g over LaAS-20, which is better than that over LaCS-20 and other La-doped reported sorbents. Furthermore, LaAS-20 adsorbent showed good stability and regeneration ability, and has potential applications to be applied in adsorptive desulfurization technology.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2026
·
IF 3.1
Hao Ruixin,Liang Jinjiang,Gao Tianyi,Yuan Qiong,Shi Hongsheng,Liu Wei,Yu Yi
Garnet-type Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) is a promising solid electrolyte, but Li dendrite penetration remains a critical challenge. Since pores and grain boundaries are often regarded as preferential sites for Li deposition, the local structure and chemistry of these regions were investigated. Zr enrichment was observed near pores and grain boundaries, and focused ion beam (FIB)-transmission electron microscopy (TEM) analysis identified the grain boundary impurity phase as Li 2 ZrO 3 , indicating that local chemical heterogeneity is closely associated with failure-sensitive regions in LLZTO. To trace the origin of this impurity phase, the precursor was further examined. La 2 O 3 was found to undergo hydration during storage, forming La(OH) 3 and introducing an effective stoichiometric deviation during synthesis, which promotes Li 2 ZrO 3 formation. After pre-annealing purification of La 2 O 3 , the impurity phase was significantly suppressed, while the relative density and critical current density (CCD) of LLZTO were both markedly improved. These results demonstrate that precursor purification is an effective strategy for improving the phase purity, relative density, and current tolerance of LLZTO. Graphical abstract Online Figure: La 2 O 3 precursor purification improves LLZTO relative density and current tolerance. Pre-annealing commercial La 2 O 3 at 900 °C for 10 h reduces hydroxide/oxycarbonate-related impurities, suppresses Li 2 ZrO 3 formation, and yields denser LLZTO ceramics with enhanced CCD.
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DOI
高影响因子
Chemical Science
·
2018
·Vol. 9
·期 14
·3426-3437
·
IF 9.063
Xinyu Li,Zhi-Jian Zhao,Liang Zeng,Jiubing Zhao,Hao Tian,Sai Chen,Kang Li,Sier Sang,Jinlong Gong
La2O3 exhibits good performance for various catalytic applications, such as oxidative coupling of methane (OCM) and dry reforming of methane (DRM), during which coke formation may lead to the deactivation of catalysts. Typically, the reaction between CO2 adsorbed on La2O3 and coke is the rate-determining step of the coke elimination process. This paper describes the influence of Ce addition on the CO2 adsorption and activation over La2O3. Combined with in situ and ex situ characterization and density functional theory (DFT) calculation, we show that Ce addition promotes the formation of bidentate carbonate on La2O3via tuning CO2 adsorption energy. In addition, Ce addition adjusts the ratio of bidentate/monodentate carbonate, and affects the ratio of hexagonal/monoclinic La2O2CO3 on the binary oxides. DRM is used as a probe reaction to examine the coke elimination performance of Ce–La binary oxide. It is found that when the Ce/La ratio reaches the optimal value (0.15), Ce–La binary oxide has the highest CO2 adsorption energy and predominantly promotes the formation of bidentate carbonate, and hence possesses the highest basicity above 700 °C and finally exhibits the best coke elimination performance.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Jinhuo Gao,Tao Yuan,Sainan Luo,Jiafeng Ruan,Hao Sun,Junhe Yang,Shiyou Zheng
In this work, a conformally interfacial nanocoating strategy is introduced to enhance the lithium ion storage performance of LiNi 0.5 Mn 1.5 O 4 (LNMO). Stable cycling of LNMO is achieved through La 2 O 3 coating at both room and elevated temperatures. A series of La 2 O 3 -coated LNMO composites with various coating contents ranging from 0 to 3 wt% is prepared, and their electrochemical behaviors are systematically investigated. Among them, the 2 wt% La 2 O 3 -coated LNMO cathode presents the best comprehensive lithium ion storage performance; for instance, it retains more than 75% capacity retention after 500 cycles at room temperature and 93% capacity retention after 50 cycles at an elevated temperature of 55 °C with 1C rate. Moreover, the modified samples show more stable plateau potential than the pristine one during the cycling process. It is believed that the introduction of the La 2 O 3 nanocoating layer can effectively suppress side reactions between electrode and electrolyte, thus maintaining stable structure of electrode material and reducing polarization during cycling. Our work provides an effective approach to improve the electrochemical stability of LNMO high-potential cathode for future large-scale applications of enhanced lithium ion batteries with high energy density and long cycle life.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2016
·Vol. 33
·期 6
·1837-1845
·
IF 1.408
Liu Dongjing,Zhou Weiguo,Wu Jiang
Performance of CeO 2 -La 2 O 3 /ZSM-5 sorbents for sulfur removal was examined at temperature ranging from 500 oC to 700 oC. The sulfur capacity of 5Ce5La/ZSM-5 was much bigger than that of CeO 2 /ZSM-5. H 2 had a negative impact on the sulfidation; however, CO had little influence on sulfur removal. The characterization results showed that CeO 2 and La 2 O 3 were well dispersed on ZSM-5 because of the intimate admixing of La 2 O 3 and CeO 2 , the major sulfidation products were Ce 2 O 2 S and La 2 O 2 S, the XRD and SEM results revealed that ZSM-5 structure could remain intact during preparation and sulfidation process, the H 2 -TPR showed that the reducibility of CeO 2 can be remarkably enhanced by addition of La.
研究领域:
材料科学
·
环境化学
·
催化化学
·
能源工程
·
无机功能材料
·
气体净化
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）