JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Yang Lyu,Hui Tang,Guangdong Zhao
Polymer-derived ceramics (PDCs), such as silicon oxycarbide and its derivatives, show an exceptional high oxidative stability under extreme conditions. A novel multicomponent silicon oxycarbide system tailoring with transition metal (hafnium) and boron is fabricated by sol-gel and solvothermal method. Amorphous SiHBOC was formed via the condensation of Si–OH, B–OH and Hf–OH groups, respectively, and the bonds of Si–O–Hf and Si–O–B– were detected by FTIR and XPS characterization. After high-temperature pyrolysis, the precursor is converted to a rigid ceramic material that has an 85.8 wt % ceramic yield of SiHfBOC. We investigate the oxidation resistance performance of SiHfBOC using the isothermal oxidation test at 1400 °C. The results showed that the oxidative stability of SiHfBOC was significantly superior to than those of SiBOC ceramic.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Mithun Nath,Shengqiang Song,Ning Liao,Tengteng Xu,Hang Liu,Himansu Sekhar Tripathi,Yawei Li
Obtaining a stable Cr 3+ phase at higher temperatures in the presence of hydraulic calcium aluminates (the phases found in calcium aluminate cement, CAC) in the Al 2 O 3 –CaO–Cr 2 O 3 system remains a significant challenge in many application areas, as the formation of toxic, carcinogenic, and water-soluble Cr 6+ compounds often occur. To address the issue, recently, we synthesized a high-temperature stable Cr 3+ ternary compound (CaAl 2 Cr 2 O 7 ) with space group P3 (143). In the present work, we investigated the formation-stability of CaAl 2 Cr 2 O 7 with in-situ calcium aluminate phases at 1500 °C under the CO 2 atmosphere in the Al 2 O 3 –CaO–Cr 2 O 3 system through solid-oxide reactions route varying Cr 2 O 3 content (at constant Al 2 O 3 :CaO ratio). It co-existed with hydraulic calcium aluminates and other phases over the full investigated composition range of 2.76–68.3 mol% Cr 2 O 3 (5–80 wt%). Apart from CAC phases (CaAl 2 O 4 , CaAl 4 O 7 ), major Cr 3+ -phases are CaAl 2 Cr 2 O 7 and (Al,Cr) 2 O 3 while (α,β)-CaCr 2 O 4 and Ca(Al,Cr) 12 O 19 formed as minor phases. At a constant Al 2 O 3 :CaO ratio of 5.6:4.4 mol% (7:3 wt%), the formation of the CaAl 2 Cr 2 O 7 phase increases with Cr 2 O 3 content (up to the investigated composition of 26.43 mol%) and then decreases gradually. The solid solubility of Al and Cr in the CaAl 2 Cr 2 O 7 phase limited over a narrow range, and presumably dependent more on heat treatment condition rather than composition as reflected from the lattice parameter calculations. Though XRD revealed the presence of only Cr 3+ -phases in the partial CO 2 atmosphere, however, traces of Cr 6+ could be detected using XPS and leaching tests. However, leachable Cr 6+ content (0.095–1.252 mg/L) were much below the United States Environmental Protection Agency (US-EPA) permissible limit of 5 mg/L. The formation mechanism of the CaAl 2 Cr 2 O 7 and other phases with plausible reactions were also discussed.
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
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Chengyi Zhu,Jianxiong Liu,Xiaohua Yu,Yingjie Zhang,Xiaodong Jiang,Peng Dong,Yannan Zhang
Spinel LiMn2O4 has attracted increasing interest as promising cathode material owing to its low cost, high safety, and environmental friendliness. But the further development of LiMn2O4 is restricted by fast capacity fading upon cycling, especially at high temperatures. Herein, the one-dimensional (1D) Li4Ti5O12 coated LiMn2O4 nanorods (LMO-LTO) are successfully prepared by combining sol-gel and solid-state calcination method and ultimately enhance the cathode utilization in high-temperature and long-cycling conditions. The as-prepared LMO-LTO cathode delivers a high initial discharge capacity of 128.5 mAh g -1 at 0.1 C rate and exhibits a promising discharge capacity over 74.5 mAh g -1 at 10 C rate. Even under an elevated temperature of 55 O C, it still maintains 74.8% of its initial capacity at 1 C rate. Furthermore, the electrochemical impedance spectra (EIS) measurement confirm that compared with the pure LiMn2O4 nanorod, lower the charge transfer resistance (Rct) and enhanced Li + diffusion coefficient are also strong evidences of the improved electrochemical performance of LiMn2O4 nanorods after Li4Ti5O12 coating.
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
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2020
·Vol. 104
·期 4
·1772-1784
·
IF 3.502
Jinxue Ding,Fengbo Chen,Jianxin Chen,Jin Liang,Jie Kong
Demand for high-performance electromagnetic (EM) wave absorbing materials with high-temperature resistance is always urgent for application in a harsh environment. In this contribution, two-dimensional material, Ti 3 C 2 T x MXene, was introduced into a hyperbranched polyborosilazane. After pyrolyzation, the as-prepared TiC/SiBCN ceramics present excellent EM wave absorption in X-band. The TiC nanograins appearing after annealing provide multilevel reflection and interface polarization. Dipole polarization formed at interface defects, in company with interfacial polarization, also makes a great contribution to enhanced EM wave absorption. The TiC/SiBCN nanocomplex prepared with 5 wt% Ti 3 C 2 T x MXene possesses a minimum reflection coefficient of −45.44 dB at 10.93 GHz and abroad bandwidth 8.4 and 12.4 GHz, almost covering the entire X-band. Tuning the thickness in the range of 2.35-2.54 mm, the effective absorption band can achieve the entire X-band. And the EM wave absorbing performance has been maintained to a large extent at 600°C with the minimum reflection coefficient of −26.12 dB at 12.13 GHz and the effective absorption bandwidth of 2 GHz. Last but not the least, TiC/SiBCN ceramics offer a good thermal stability in argon as well as in air atmosphere, making it possible to serve in high-temperature detrimental environments. This study is expected to provide a new perspective for the design of high-performance absorbing materials that are able to be used in harsh environments, especially in high temperatures.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 14
·7645-7651
·
IF 3.049
Xin Wang,Min Xue,Songbai Liu,Kuo Jiang,Zhuli Zhang
Herein, powders composed of La2Zr2O7 (LZ) and ZrO2 phases were synthesized by an in situ reaction using a sol-spray pyrolysis method; moreover, 24 mol% LaO1.5–ZrO2 (volume ratio = 1 : 1) powders were characterized by XRD, Raman spectroscopy, SEM, and TEM. XRD and Raman results showed that the samples maintained a tetragonal ZrO2 and a pyrochlore LZ phase from 900 to 1100 °C. The addition of LZ could be helpful in the stabilization of t-ZrO2 and decreasing the grain size of ZrO2. The SEM results revealed that the LZ and ZrO2 phases were homogeneously distributed in the sintered bulk. The HRTEM results suggested that the crystal orientations of the nano-LZ and nano-ZrO2 phases were accordant; this was in agreement with the characteristics of the coherent boundaries. The fracture toughness of LZ–ZrO2 was markedly improved by the transformation toughening of the ZrO2 phase, and a value that was 2.2-fold that of the LZ prepared by a similar technique was achieved.
研究领域:
材料科学
·
陶瓷学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2018
·
IF 2.447
Xin Wang,Min Xue,Songbai Liu,Kuo Jiang
In this paper, (Gd 1− x Ce x ) 2 Zr 2 O 7+ x immobilized matrices with high cerium (Ce) amount-of-substance fractions (up to 90%) were prepared by sol-spray pyrolysis , and then sintered at 1600 °C in air. XRD results showed that all samples were in a mixture of pyrochlore and fluorite phase, even after sintering at 1600 °C. All the sintered bulks were dense, and the densities were independent of the additive content . The SEM results showed that all samples were chemically homogeneous. There was no segregation in the grain boundary. EDS quantification yielded a mean composition close to the stoichiometric chemical composition.
研究领域:
材料科学
·
核废料管理
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2023
·Vol. 39
·期 6
·1084-1091
·
IF 3.1
Gao Zhuangzhuang,Li Baoju,Ou Shuxian,Li Dongsheng,Fang Qianrong,Qiu Shilun,Xue Ming
M etal-organic frameworks (MOFs) are attractive in membrane separation due to their special pore structure and suitable aperture size. The fabrication of defect-free and robust MOF membranes with excellent durability is highly demanded but remains challenging. In this work, we report a one-step active γ -alumina conversion strategy for the facile and reliable fabrication of an MIL-96 membrane. In this case, the γ -Al 2 O 3 sol was dip-coated and sintered on the α -Al 2 O 3 disc as the active aluminum source and substrate for the nucleation and growth of MOF. A continuous and well-intergrown MIL-96 membrane was generated with exceptional stability due to the strong adhesion to the substrate. The resultant MIL-96 membrane yielded a satisfactory H 2 /CO 2 permselectivity and high-temperature resistance, delivering a selectivity of 12.35 with H 2 permeance of 6.20×10 −7 mol·m −2 ·s −1 ·Pa −1 at 150 °C. Moreover, the probe membrane presented remarkable durability and recyclability under harsh hydrothermal conditions. This method paves the way for constructing highly stable and selective MOF membranes and could accelerate the development of advanced membrane separation technologies for gas purification and recycling in addressing the severe energy and environmental problems.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Physics
·
2024
·
IF 10
Biao Zhang,Liming Quan,Zhihong Luo,Qiantong Li,Jianming Deng,Shuhang Yu,Wangxin Li,Mingmei Lin,Feng Yan,Dawei Wang,Dongyan Yu,Changbai Long,Laijun Liu
CaBi 2 Nb 2 O 9 (CBNO) ceramics exhibit significant potential in the development of piezoelectric sensors suitable for extreme environments such as aerospace, metallurgy, and nuclear power plants. While previous studies have enhanced the piezoelectric response of CBNO ceramics, their insulating properties at high temperatures still require improvement. In this work, co-substitution of (Li 0.5 Bi 0.5 ) at A site and Mn at B site was designed to improve the electrical properties of CBNO ceramics. Defect dipoles induced by the bound between Mn and oxygen vacancies restrict the movement of oxygen vacancies at high temperatures. Meanwhile, co-substitution of Ca by (Li 0.5 Bi 0.5 ) reduces both the sintering temperature and volatilization of Bi 2 O 3 during the sintering process. This modification results in an ultra-high T C of 928 °C and an exceptional resistivity of 2.85 MΩ cm at 600 °C for Ca 0.96 (Li 0.5 Bi 0.5 ) 0.04 Bi 2 Nb 1.98 Mn 0.02 O 9 ceramics. Furthermore, the ceramic exhibits excellent piezoelectric properties ( d 33 of 15.2 pC/N and k p of 6.9 %), ferroelectric properties ( P r of 9.42 μC/cm 2 ), and thermal stability (degeneration of d 33 only 6 % after annealing at 900 °C for 2 h). This work offers a practical strategy for simultaneously achieving both a high piezoelectric response and outstanding insulating properties in the CBNO system.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 18
·8967-8977
·
IF 6.97
Li Li,Rui Zhao,Tinghua Xu,Dandan Wang,Du Pan,Kun Zhang,Caiyan Yu,Xia Lu,Guanjie He,Ying Bai
LiNi0.5Mn1.5O4 (LNMO) spinel has drawn increasing attention due to its high voltage, stabilized electrochemical performance and safety features as a cathode for lithium-ion batteries. However, the main challenge lies in its unstable surface structure, especially at elevated temperatures. In this paper, we decorate the LNMO precursor with a solid electrolyte of Li1.4Al0.4Ti1.6(PO4)3 (LATP) via a facile sol–gel method, followed by a co-crystallization process at 820 °C, to successfully generate a LATP modification shell at the surface of LNMO. The LATP modification shell could not only optimize the morphology of LNMO including the limitation of particle growth and control of crystalline orientation, but also realize ion doping during the co-crystallization process. By tuning the LATP contents, the 2 wt% LATP modification is found to be the most effective at balancing the interfacial stability and Li+ diffusion kinetics of LNMO, as well as enhancing its rate capability and capacity retention at high temperatures. As a result, the 2 wt% LATP-modified LNMO cathode exhibits a high reversible capacity of 84.8 mA h g−1 after 500 cycles with a capacity retention of 68.9%, and a superior rate capability (102.0 mA h g−1 at 20 C) at room temperature. Moreover, this electrode also delivers a good capacity retention of 85.7% after 100 cycles at 55 °C, which is ascribed to the stabilized interface with a LATP protective layer.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2023
·
IF 2.2
Yuanzhi Qu,Wenchao Zhang,Han Ren,YueHui Yuan,Xinyu Zhou,Gang Yang,Xianfa Zhang
Deep oil and gas are essential alternative resources for future energy sources, but the lack of high temperature and high salt resistance mechanisms and agents significantly limits their development. Copolymers of six commonly used high-temperature and salt resistance monomers and acrylamide with similar molecular weights were prepared to improve oil recovery in deep reservoirs. The effects of different functional groups on the high-temperature and salt resistance of polymers were revealed by the drilling fluid and elemental analysis, TOC test, Zeta potential, particle size, and other analytical methods. Experimental results indicate that the pyrrole ring groups, quaternary amine groups, long-chain sulfonate groups, and benzenesulfonic acid groups can effectively improve the high-temperature stability of polymers in an aqueous solution. Quaternary ammonium groups and pyrrole rings can enhance the polymer adsorption with clay under high temperatures and high salinity conditions due to charge attraction. However, these functional groups hinder the clay dispersion and reduce the stability of drilling fluids. Hydration groups, such as sulfonic and carboxylic acid groups, can better maintain the colloidal stability of drilling fluids under high temperatures and high salinity, and benzene sulfonic acid groups are the optimal hydration groups. After the polymer is adsorbed on the clay surface, the benzene sulfonic acid group assists in forming a thicker hydration film on the clay surface, effectively hindering the damage of high temperature and high salinity on the clay. The findings and observations of this study provide theoretical support for the development of high-temperature and salt resistance polymers for water-based drilling fluids of ultra-deep wells.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2024
·
IF 9.7
Lili Yang,Chong Li,Yun Da,Jinrui Zhang,Gang Wang
Concentrated solar power (CSP) is a green energy technology that efficiently harnesses solar energy. Solid particles constitute the key medium for solar photothermal conversion and storage. However, drawbacks such as high thermal radiation loss and poor high-temperature stability limit their application. This paper proposes solid particles based on steel slag for highly efficient and durable selective sunlight absorptance and thermal storage. Raw pellets are obtained via a simple extrusion and rolling process, and sinter them to derive solid particles. These particles exhibit excellent selective solar absorption characteristics and have good potential for efficient heat storage. The average solar absorption of the solid particles sintered at 1310 °C reaches 93.20%, and the emissivity at 700 °C is 80.25%. Furthermore, the specific heat and the thermal conductivity of wafer-like materials are 1.09 J/(g·K) and 2.92 W/(m·K), respectively. In addition, the solid particles are arranged for exhaustive and harsh high-temperature durability tests, and they exhibit an ultra-stable solar weighted absorptance of 93.25 ± 0.09% (mean ± standard deviation), excellent resistance to thermal shock, and superior abrasion resistance. Moreover, the low cost and simplicity of the process greatly enhance the scalability of steel-slag-based solid particles. In summary, by innovatively addressing the challenges faced by solid particles, such as high radiative heat loss, poor heat storage capacity, and high-temperature instability, this study accumulates an advantage in the competition with phase-change and thermochemical materials, and greatly improves the feasibility of using solid particles in large-scale applications.
研究领域:
材料科学
·
可再生能源
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Xiao Zhang,Zhanyi Wang,Jianan Deng,Honghao Zhao,Yuan Zhuang,Ziyi Zhang,Xiuxia Sun,Haoyu Lian,Miao Han,Yongjun Tian
In recent years, new technologies involving self-suspending proppant (SSP), which improves proppant distribution, reduces the use of chemicals in fracturing fluids, and simplifies the fracturing construction process, have become a focus of hydraulic fracturing research. However, the available products have poor suspension stability, cannot withstand high temperature and salt environments, and are highly damaging to reservoirs. In this study, we presented a novel self-suspending (HTS-SSP) proppant with excellent suspension stability, temperature resistance, and salt resistance, prepared from quartz sand, silane coupling agent, and modified polyacrylamide to achieve these properties. Wettability tests, surface morphology analysis, and Fourier transform infrared spectroscopy analysis proved that 3-methacryloxypropyltrmethoxysilane (KH570) successfully modifies quartz sand, and the HTS-SSP was synthesized. In terms of the suspension performance, HTS-SSP exhibited exceptional suspension stability due to the incorporation of KH570. It remained suspended at 150 °C or 24 wt % brine and showed excellent temperature and salt resistance. The gel-breaking fluid of the surface polymer of HTS-SSP had low damage to the reservoir, much less than the guar gum fluid. The difference between the conductivity of the aggregate remaining after HTS-SSP gel-breaking and that of unmodified quartz sand was not significant. The synthesized HTS-SSP demonstrates outstanding comprehensive performance and is an ideal candidate for reservoir development under harsh temperature and salinity conditions.
研究领域:
石油工程
·
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）