Materials
·
2022
·Vol. 15
·期 24
·8971
·
IF 3.748
Yaohui Xu,Liangjuan Gao,Zhao Ding
Doping CeO2with Y cations was achieved in this study using three strategies: doping only during the hydrothermal process (H-Y-doped CeO2), doping only during the impregnation process (I-Y-doped CeO2), and doping during both the hydrothermal and impregnation processes (H/I-Y-doped CeO2). During the three synthesis strategies of Y-doped CeO2, these Y ions could be incorporated into the CeO2lattice in the +3 state while holding the cubic fluorite structure, and no impurity phases were detected. Pure CeO2crystal itself contained a certain number of intrinsicVOdefects, and Y-doping was beneficial for the creation of extrinsicVOdefects. The relative concentrations ofVOdefects were quantified by the values ofA592/A464obtained from Raman spectra, which were 1.47, 0.93, and 1.16 for the H-Y-, I-Y-, and H/I-Y-doped CeO2, respectively, and were higher than that of the undoped one (0.67). Moreover, the OSCs of the three Y-doped CeO2were enhanced, and the sequence of OSCs was: H-Y-doped CeO2(0.372 mmol/g) > H/I-Y-doped CeO2(0.353 mmol/g) > I-Y-doped CeO2(0.248 mmol/g) > Undoped CeO2(0.153 mmol/g); this result was in good agreement with the Raman spectroscopy results.Keywords:CeO2;rare-earth;doping;hydrothermal;impregnation;oxygen storage capability
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainable Energy Technologies and Assessments
·
2021
·
IF 5.353
Aixia Chen,Zheng Tian,Rong Han,Xiao Wei,Ruirui Hu,Yang Chen
In this study, a nickel (Ni)-based catalyst was loaded onto steel slag that was rich in metal oxides using impregnation method. The effects of the catalyst on hydrogen-rich gas produced using sludge steam gasification were discussed. Under the conditions of 900 ℃, steam flowrate of 1.5 g min −1 and 20% Ni-based loading rate, the gas and H 2 yield reached 0.78 Nm 3 kg −1 and 15.72 mol kg −1 . At this time, the volume fraction of H 2 was as high as 45.096%. Compared with the raw sludge gasification without Ni-based catalyst, the gas and H 2 yield were increased by 39.22% and 60.15% respectively. However, excessive flowrate of steam (≥1.5 g min −1 ) and excessive rate of loading of Ni-based (≥25%) catalyst would lead to a decrease in the production of gas. In addition, the impregnation method could effectively disperse NiO particles on the surface of the support, increasing the ratio of active sites on the surface of catalyst and improving the catalytic activity. These characteristics indicated that the Ni-based steel slag catalysts prepared by the impregnation method had high application potential in the process of sludge steam gasification, and provided a novel idea for solid wastes recycling.
研究领域:
环境科学
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能源工程
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 29
·15299-15306
·
IF 7.443
Jugong Zheng,Cancan Qin,Tongfu Wu,Shuangfei Xie,Liang Ni,Muyang Peng,Yuefeng Tang,Yanfeng Chen
Preparing high-performance LiMnPO4 is still a large obstacle due to its sluggish electrochemical kinetics. To overcome this problem, a novel method is developed for LiMnPO4/C nanoplates from nanoporous Mn2O3 precursors. There are two advantages. Firstly, through negative pressure immersion, lithium dihydrogen phosphate (LiH2PO4), lithium hydroxide (LiOH) and sucrose (C12H22O11) are deposited on the surface of porous Mn2O3 nanosheets. In the following solid-state reaction, three dimensional continuous conductive carbon is wrapped uniformly around the LiMnPO4/C nanoplates, which greatly improved the conductivity. Secondly, (010) exposed facets are obtained using the Mn2O3 hierarchical microspheres as precursors, which allows for a fast transmission of Li+ ions improving the rate capability. As a result, the as-synthesized L-Mn2O3-LMP/C samples exhibit a superior rate performance with discharge capacities of 157.3 mA h g−1 at C/20, 122.6 mA h g−1 at 1C, and 105.8 mA h g−1 at 2C. Meanwhile, they can retain 99.3% of the initial capacity after 100 cycles at 1C, revealing an excellent cycling stability. This method sheds more light on the fabrication of high-performance LiMnPO4/C cathode materials and is suitable for large scale productions.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Na Rao,Mei Wang,Ziming Shang,Yanwen Hou,Guozhi Fan,Jianfen Li
Modifications by impregnation and grafting are commonly used for the preparation of amine-functionalized MCM-41. A comprehensive evaluation of the advantages and disadvantages of the two methods was performed in this work. MCM-41 was synthesized by the hydrothermal method, setting the amine-loading mass fraction at 40, 50, and 60 wt %. Three amine-modified adsorbents were prepared by impregnating polyethylenimine (PEI), and the three other adsorbents were prepared by grafting 3-aminopropyltriethoxysilane (APTS) onto MCM-41. The as-prepared adsorbents were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and N2 adsorption–desorption techniques. CO2 adsorption capacities were measured, and the experimental data were fitted with adsorption kinetic models. The cyclic stability of the adsorbents prepared by the two kinds of amine-modified methods was compared using the cyclic adsorption–desorption experiments. The characterization results showed that the target adsorbents were prepared successfully. The thermal stability of the adsorbents modified by grafting was better than the thermal stability of the adsorbents modified by the impregnation. Maximum CO2 adsorption capacities of 3.53 mmol g–1 (50% PEI–MCM-41) and 2.41 mmol g–1 (50% APTS–MCM-41) could be reached at 25 °C and 1 atm, which were 4.7 and 3.2 times greater than that of MCM-41. The Avrami model fitted the experimental data well, indicating a variety of interactions between the adsorbents and CO2. CO2 adsorption capacity after 5 adsorption–desorption cycles decreased by 14.22 and 5.19% for the adsorbents prepared by impregnation and grafting, respectively. It was concluded that MCM-41 modified by impregnation and grafting followed the same kinetic model. The absorbents modified by impregnation showed higher CO2 adsorption capacity and amine-loading efficiency, while those prepared by grafting had better thermal and cyclic stabilities.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
APPLIED ENERGY
·
2016
·
IF 5.746
Peizhao Lv,Chenzhen Liu,Zhonghao Rao
In this paper, different particle sizes of kaolin were employed to incorporate paraffin via vacuum impregnation method. The paraffin/kaolin composites were characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimeter (DSC) and Thermogravimetry (TG). The results showed that the paraffin/kaolin composite with the largest particle size of kaolin (K4) has the highest thermal conductivity (0.413 W/(m K) at 20 °C) among the diverse composites. The latent heat capacity of paraffin/K4 is 119.49 J/g and the phase change temperature is 62.4 °C. In addition, the thermal properties and thermal conductivities of paraffin/K4 with different mass fraction of K4 (0–60%) were investigated. The thermal conductivities of the composites were explained in microcosmic field. The phonon mean free path determines the thermal conductivity, and it can be significantly affected by temperature and the contact surface area. The leaks, thermal storage and release properties of pure paraffin and paraffin/kaolin composites were investigated and the composites presented good thermal stabilities.
研究领域:
材料科学
·
热能工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2023
·Vol. 170
·期 3
·034506
·
IF 3.9
Shihang Guo,Yifeng Li,Donglin Han
Due to the large polarization resistance (Rp) of positrodes (namely, air/steam electrodes), it is vital to develop high-performance and cost-effective positrodes to improve the performance of protonic ceramic cells (PCCs). In this work, we report a La1.2Sr0.8NiO4+δ (LS8N) positrode decorated with (La,Sr)CoO3-δ (LSC) nanoparticles by infiltrating Co(NO3)2 solution. Rp of a bare electrode was 4.22 Ωcm2 at 600 °C, and reduced by almost ten times to 0.49 Ωcm2 by infiltrating with a 0.2 molL−1 Co(NO3)2 solution. Furthermore, although Rp of the bare electrode increased after a durability test by exposing to Ar—20% O2–3% H2O at 600 °C for 100 h, Rp of the infiltrated electrode further decreased after the durability test. For example, Rp of the electrode infiltrated with 0.2 molL−1 Co(NO3)2 solution reduced to 0.37 Ωcm2, which is attributed to the enhancement of the LSC/LS8N interface. The good electrochemical performance and durability of the positrodes with LSC/LS8N heterogeneous interface, which can be optimized by controlling the parameters for the infiltration process, suggest a potential strategy for designing excellent positrodes for PCCs.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Laiquan Lv,Jiankang Wang,Mengting Ji,Yize Zhang,Shengyao Huang,Kefa Cen,Hao Zhou
In this article, waste phoenix leaf biochar was introduced into three most used organic phase change materials (PCMs) to prepare shape-stable composite PCMs by the vacuum impregnation method. The encapsulation capacity and encapsulation efficiency of steam activated biochar for paraffin, stearic acid, and polyethylene glycol were 59.28% and 49.14%, 63.03% and 57.62%, 71.38% and 46.84%, respectively, which was related to the mechanisms of biochar encapsulated organic PCMs. The dominant mechanisms of biochar encapsulated organic PCMs are summarized as pore-filling, hydrogen-bonding, hydrophobic interaction between biochar and PCMs, and other potential mechanisms. Influence degree η was introduced to illustrate the effect of biochar on organic PCMs, 16.56%, 8.72%, and 35.75% for steam activated biochar on paraffin, stearic acid, and polyethylene glycol. In addition, compared with original PCMs, the thermal conductivity of biochar-based composite PCMs first decreased and then increased with the increase of biochar pyrolysis temperature. Moreover, biochar-based composite PCMs had better thermal stability, concerned with the dominant mechanisms of biochar encapsulated organic PCMs. Therefore, biochar-based composite PCMs proposed in this study expand the application of biochar and organic PCMs in thermal energy storage , building energy conservation , solar energy utilization, and battery thermal management system .
研究领域:
能源材料
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2021
·Vol. 105
·期 1
·181-192
·
IF 3.784
He Li,Yongsheng Liu,Paolo Colombo,Wenbo Li,Yansong Liu,Kehui Hu,Zhigang Lu
3D-printed alumina ceramic cores often face the problem of low flexural strength at its application temperature of 1500℃, and the requirements on porosity and strength limit its fabrication process. In this research, three types of solutions were employed to impregnate the ceramics to improve the strength of the 3D-printed alumina ceramic cores. The results showed that silica sol (SS), tetraethyl orthosilicate (TO), and 3-(Trimethoxysilyl)propyl methacrylate (PM) all could improve the (room temperature) flexural strength of the 3D printed ceramics effectively compared to the control sample (CS) without impregnation, and the SS solution could improve the high temperature flexural strength at 1500℃ greatly compared to other solutions. The improvement in strength was due to the introduction of Si, which formed a stable mullite phase during the sintering process. Computed tomography (CT) analysis showed there is no cracks formed in the ceramic cores impregnated with the SS solution, and they exhibited the overall best performance (21.2 ± 0.8 vol% open porosity, shrinkage of 3.2 ± 0.3% in the X direction, 3.4 ± 0.2% in the Y direction, 2.1 ± 0.4% in the Z direction, room temperature flexural strength of 85.7 ± 6.9 MPa, and 1500℃ flexural strength of 19.2 ± 1.1 MPa).
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Xiao Sun,Yujiang Sun,Shunjin Yang,Xiaohu Hu,Yifan Yan,Dehang Ren,Haoran Qian,Ligang Wang,Boyang Chong,Yu Jiang,Kemeng Ji,Yongan Yang
Lithium-sulfur batteries (LSBs) are among the most promising systems beyond lithium-ion batteries. For assembling LSBs, compared with the sulfur (S) cathodes, the lithium sulfide (Li 2 S) cathodes are disadvantageous in their incapability of using the melting-impregnation technique due to the high melting-point of Li 2 S. This paper reports a special melting-impregnation method for preparing Li 2 S cathodes, by utilizing the fluidic property of dimethoxyethane-adducted lithium polysulfides (Li 2 S n ) at 110°C. After the tannic-acid etched cobalt-organic-framework ZIF-67 is impregnated with such fluid and further calcined, the obtained h-Li 2 S@C67 materials present a 34% better performance vs. the commercial Li 2 S-derived c-Li 2 S@C67 cathode. Moreover, its capacity can be increased by 10%, when soaked in pyrrolidine and then heated to carbonize pyrrolidine. Major factors for the performance improvement include the catalytic effect of Co atoms on the charging/discharging kinetics between Li 2 S and S, the increased surface area via tannic acid etching, the enhanced conductivity from the ZIF- and pyrrolidine-derived carbon, and the self-catalytic Li 2 S@Li 2 S 2 @Li 2 S 6 double-shell structures derived from the calcined Li 2 S n .
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Ben Chen,Bowen Hui,Yuting Dong,Qiang Sheng,Xiang Li,Qinglan Hao,Chunjing Liu
The SiO 2 - and MCM-41-supported Ni catalysts were prepared by an incipient wetness impregnation method and their performance in the hydrogenation of liquid organic hydrogen carrier were evaluated using N-ethylcarbazole (NEC) as model compound. Ni particles were mainly located on the external surface of the SiO 2 -supported Ni catalysts. Both Ni particles on the external surface and filled in the mesopores of MCM-41 were found in the MCM-41-supported catalysts. The reduction of surface Ni particles occurred at low temperature (ca. 365 °C), but the complete reduction of Ni particles in the mesopores of MCM-41 required high temperature (ca. 555 °C). The MCM-41-supported Ni particles possessed lower electron densities than the SiO 2 -supported ones. The surface Ni particles showed the same activity in the hydrogenation of NEC, which were more active than those in the mesopores of MCM-41. A correlation between the electron density of Ni particles and their selectivity was observed. The higher the electron density of Ni particles, the higher the selectivity to the fully hydrogenated product (dodecahydro-N-ethylcarbazole) is.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2022
·Vol. 15
·期 5
·1717
·
IF 3.748
Wei Li,Conghui Guo,Congcong Cui,Jianxun Bao,Ge Zhang,Yubei Zhang,Shan Li,Gong Wang
The high topological silicon carbide (SiC) ceramics can be prepared by stereolithography (SLA) combined with liquid silicon infiltration (LSI) techniques. This paper aims to enhance the performance of SiC ceramics prepared by SLA and LSI techniques via the cyclic impregnation/carbonization of the precursor of carbon source solution before LSI. The effects of impregnation/carbonization cycles on the microstructure and properties of C/SiC preform and sintered body were analyzed in detail. The results show that, with the increase of impregnation/carbonization cycles, the porosity in the C/SiC preform decreases obviously and the content of secondary SiC in the sintered body increases effectively. Especially, when the impregnation/carbonization cycle was performed twice, the sintered body had the optimal mechanical properties. The value of flexural strength, bulk density and elastic modulus were 258.63 ± 8.33 MPa, 2.95 ± 0.02 g/cm3and 425.16 ± 14.15 GPa, respectively. In addition, the thermal dimensional stability of sintered body was also improved by this method. This method proves that SiC ceramics prepared by SLA combined with LSI have the potential of applications in space optical mirrors.Keywords:impregnation method;liquid silicon infiltration;microstructure evolution;mechanical properties;SiC ceramics
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF THERMOPHYSICS
·
2023
·Vol. 44
·期 10
·1-18
·
IF 2.2
Li Yan,Wang Shuo,Tan Wangwang,Zhou Shenghui,Zhu Qunzhi
Erythritol (ET) is a promising medium–low temperature organic phase change material. To solve the problems of supercooling, leakage, and low thermal conductivity, expanded graphite (EG) with four different particle sizes of 32 mesh, 50 mesh, 80 mesh, and 100 mesh was used as supporting material. A shape-stabilized composite phase change material (CPCM) with a mass ratio of EG to ET of 9:1 was prepared by the ultrasonic impregnation method. The properties were tested and analyzed by DSC, SEM, FTIR, XRD, and TGA. The experimental results showed that 50 mesh EG was more suitable as an adsorption carrier for erythritol among the four different particle sizes of EG. Compared with pure erythritol, the supercooling degree of 50 mesh EG/ET composite decreased by 35.2 %, the latent heat of solidification increased by 8 %, and the thermal conductivity increased by 250.8 %, which increased the heat storage and release capacity of the material by 19.2 %, and the 50 mesh EG/ET composite phase change material had good thermal stability. In this study, the relationship between the supercooling degree of EG/ET and EG particle size was analyzed, and EG/ET thermal storage materials with high thermal storage density and exothermic density were prepared. It helps to promote the application of EG-based composite thermal storage materials and the development of thermal storage technology.
研究领域:
材料科学
·
热能工程
✓ 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）