IONICS
·
2020
·Vol. 27
·期 1
·269-277
·
IF 2.394
Zheng Qian,Zhang Heng,Meng Bin,Liang Wenke,Li Chen,Ping Xinyu,Xia Zhidong
Magnesium oxide can be added into Gd-doped CeO 2 (GDC) as a suitable sintering additive, and the continuous GDC/MgO heterogeneous interface will contribute to the promotion of the oxygen ion transmission. GDC-50vol%MgO composite ceramics were sintered at different temperatures (1350~1500 °C). The phase composition, micromorphology, and electrical conductivity of GDC-50vol%MgO were analyzed by XRD, SEM, TEM, and electrochemical impedance, respectively. There are only GDC and MgO phases in the ceramics sintered at 1350 °C, 1400 °C, 1450 °C, and 1500 °C. As the sintering temperature rises from 1350 to 1500 °C, the average grain size of GDC and MgO increases from 239/274 to 680/651 nm, respectively. The GDC/MgO heterogeneous interface is clear, and many edge dislocations form there. The grain boundary and total conductivities decrease significantly with the rising sintering temperature, and the GDC/MgO heterogeneous interface possesses a higher electrical conductivity than the GDC/GDC homogeneous interface.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Xinxin Wei,Jing Zhang,Lei Wang,Yan Bai,Jingwei Huang,Houde She,Qizhao Wang
To address the issue of inefficient charge transfer efficiency at the semiconductor/cocatalyst interface, we engineered a BiVO 4 /MgO/FeCo 2 O 4 array, incorporating a MgO interlayer. This design aimed to enhance the performance of photoelectrochemical (PEC) water splitting on BiVO 4 and FeCo 2 O 4 . The introduced interlayer efficiently hinders hole backflow, promoting unimpeded charge migration within the multi-hybrid structure. This, in turn, significantly reduces the recombination of electron-hole pairs. In addition, the BiVO 4 /MgO/FeCo 2 O 4 undergoes a low-temperature plasma treatment, resulting in super-hydrophilicity. This treatment enhances charge migration efficiency and fosters extensive contact between the electrolyte and electrode interfaces. Photoelectrochemical analysis demonstrates that H-BiVO 4 /MgO/FeCo 2 O 4 exhibits exceptional performance for the oxygen evolution reaction (OER), showcasing a photocurrent density of 4.3 mA·cm −2 at 1.23 V vs. RHE in 0.5 M Na 2 SO 4 under AM 1.5 G (100 mW·cm −2 ) illumination. Remarkably, this value is 5.2 times higher than that observed for BiVO 4 . Furthermore, the maximum incident photon to current conversion efficiency (IPCE) reaches an impressive 61.7 %, surpassing that of BiVO 4 and BiVO 4 /FeCo 2 O 4 by approximately 5.1 and 1.7 times, respectively. Additionally, the charge separation efficiency of H-BiVO 4 /MgO/FeCo 2 O 4 achieves a notable 83.4 %, and the charge injection efficiency is substantially improved. This study advocates for a straightforward yet highly effective approach to mitigate interfacial electron-hole recombination.
研究领域:
材料科学
·
能源科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2018
·Vol. 33
·期 2
·381-388
·
IF 0.524
Shi Minxian,Chen Xia,Fan Shanshan,Shen Shirley,Liu Tianxiang,Huang Zhixiong
Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al 2 O 3 -SiO 2 /boron phenol formaldehyde resin (MAS/BPF) composites to lower the formation temperature of eutectic liquid phase and promote the ceramification of ceramifiable composites. The effects of fluxing agents on the thermogravimetric properties, phase evolution, and microstructure evolution of MAS / BPF composites were characterized by TG-DSC, XRD and SEM analyses. The results reveal that the addition of a fluxing agent highly reduces the decomposition rate of MAS / BPF composites. Fluxing agents lower the formation temperatures of liquid phases of ceramifiable MAS / BPF composites obviously, and then promote the ceramification and densification process. The final residues of composites are ceramic surrounded by large amount of glass phases.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2019
·
IF 4.959
Cijun Shuai,Jun Zan,Youwen Yang,Shuping Peng,Wenjing Yang,Fangwei Qi,Lida Shen,Zongjun Tian
The poor interfacial bonding and resultant agglomeration of nanoparticles in polymer-based composite severely deteriorated their reinforcement effect. In this work, MgO nanoparticles (MgO-NPs) were surface modified with Poly (L-lactic acid- co -malic acid) (PLMA) to improve the interfacial compatibility in Poly-l-lactic acid (PLLA) scaffold manufactured by selective laser sintering. PLMA possess a hydrophilic end with carboxyl group (comes from the malic acid) and an l-lactic acid chain. On one hand, the carboxyl group was able to form hydrogen bonding with the hydroxyl groups of MgO-NPs. On the other hand, the l-lactic acid chain containing the hydroxyl groups could react with the carboxyl group of PLLA. Results revealed that the scaffold exhibited significantly enhanced compressive strength and modulus by 47.1% and 237.7%, respectively, which could be ascribed to the enhanced interfacial bonding between PLLA and MgO-NPs, as well as the rigid particle reinforcement. In addition, the scaffold was favorable for cell adhesion, proliferation and differentiation, owing to the improved hydrophilic and suitable pH environment. It was suggested the scaffold was a promising material for bone repair application.
研究领域:
生物材料学
·
组织工程学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2017
·
IF 0
Quan Wang,Tuo Li,Pengfei Xie,Jiahai Ma
In this study, the interface effects of Cu 2 O and Au/Cu 2 O semiconductors were improved by addition of a magnesia (MgO) interface nanolayer (MIN) deposited via precipitation. The morphologies, crystal structures, chemical compositions, elemental states and optical properties of MgO/Cu 2 O and Au/MgO/Cu 2 O heterojunctions were characterized via SEM, XRD, XPS, UV–VIS–NIR and PL. It was found that the MIN has a surface passivation effect that inhibits the aggregation and oxidation of Cu 2 O. This enhances Cu 2 O semiconductors’ wettability and stability, improves crystallinity and reduces Au particle sizes. More importantly, the MIN promotes charge transfer via tunneling through the insulator, and enhances adsorption of molecular oxygen, facilitating superoxide radicals formation during photoreactivity. MgO/Cu 2 O and Au/MgO/Cu 2 O exhibited superior photodegradation of methyl orange, attributed to the boost of O 2 − and h + . This work confirmed the importance of MIN as a useful modification of semiconductor photocatalysts, and the MIN can significantly enhance the production of superoxide radicals in the photocatalytic activity with visible light.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Chonghe Xu,Kangkang Yuan,Xiaotong Jin,Zhichao Yu,Lei Zheng,Yadong Lü,Xinqiang Wang,Luyi Zhu,Guanghui Zhang,Dong Xu
MgO nanofiber with good morphology was difficult to obtain through high temperature heat-treatment due to the widely existed pulverization phenomenon, which restricted its applications in the high-temperature field. In this work, MgO nanofibers were prepared by electrospinning through mixed precursors: magnesium acetate (MA) and magnesium citrate (MC). The fiber with MC mass content in the range of 30–50% exhibited good high-temperature stability and the original feature was preserved after heat-treated at 1000 °С. A plausible formation mechanism of the polycrystalline MgO nanofibers was provided in the present paper. Suitable confection of MA and MC brought a milder decomposition process and led to a more compact structure of MgO nanofiber, which contributed to the excellent high-temperature stability. The considerable effects of microstructure on thermal conductivity of the fiber were discussed. The method in this paper has greatly expanded the solution scope for preparing electrospun fibers with expectation of structure modification and strength enhancement.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 11
·10651-10659
·
IF 2.195
Huang Xuechen,Liu Bang,Wang Shuanghu,Liu Yuxi,Wu Gang
Bi 2 O 3 - and MgO-doped BaTiO 3 –(Na 1/4 Bi 3/4 )(Mg 1/4 Ti 3/4 )O 3 (BT–NBMT) ceramics were synthesized from a solid-state approach, and then the impacts of Bi 2 O 3 and MgO dosages on the structures and dielectric characteristics were studied. Obvious dual peaks were observed with Bi 2 O 3 dosage to 0.04 and MgO dosage to 0.02. The low-temperature dielectric stability and grain size of the Bi 2 O 3 dopant were improved, while those of the MgO dopant hardly changed with MgO dosage to 0.02, indicating the core/shell microstructure of BT–NBMT was formed following the dissolving-precipitating mechanism of BT systems doped with low-melting-point substances. The low-temperature dielectric stability of the Bi 2 O 3 - or MgO-doped BT–NBMT ceramics first improved and then deteriorated with the increase of doping concentrations. High-temperature stability and diffuse-state transition were found in the optimal ceramics. The second phases of Bi 2 O 3 and MgO, magnesium titanium compounds were observed in Bi 2 O 3 and MgO dopants, respectively. Bi 2 O 3 -doped and MgO-doped ceramics exhibited a fine-grained microstructure and significant grain growth, respectively, and the core/shell microstructure was responsible for the dielectric temperature stability for Bi 2 O 3 dopants and collapsed to a homogeneous one with remarkable grain growth and the second phases for MgO dopants.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Fengchun Gong,Zhen Huang,Xiaolan Wei,Shule Liu,Jianfeng Lu,Jing Ding,Weilong Wang
Rapid and strong CO 2 capture is critical in CO 2 capture and utilization (CCU) techniques to mitigate global warming. Alkali molten salt (AMS) promoted-MgO sorbents with high capacity attracted attention, but their applications suffer from various limitations of low adsorption kinetics and poor stability. Here, AMS-promoted MgO sorbents corporation with Fe 2 O 3 (Mg 100-x Fe x -AMS 10 ) were fabricated via modified methanol evaporation-induced surface precipitation for use in rapid and stable CO 2 capture. Based on characterization of the sorbents, Mg 98 Fe 2 -AMS 10 showed a loose flake structure, with a large surface area and numerous exposed active sites. Therefore, Mg 98 Fe 2 -AMS 10 exhibited a strong CO 2 capacity (14.86 mmol CO2 /g sorbent at 300 °C) and good cyclic durability. Three kinetic models were explored, and the Avrami model provided a good prediction of the CO 2 adsorption behavior, with Mg 98 Fe 2 -AMS 10 exhibiting rapid adsorption kinetics. The adsorption mechanism was investigated using density functional theory (DFT) calculations. The charge transfer and bonding strengths of the surface O atoms on MgO increased, and these atoms preferentially bonded with activated CO 2 (CO 2 ∙− ) under Fe catalysis. This study may provide insights into enhancing the CO 2 capture and kinetics of MgO via combination with 3d transition metals.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2023
·Vol. 24
·期 8
·7649
·
IF 5.6
Yanjing Liu,Xiyue Li,Yuezhou Liu,Yaping Huang,Fuming Wang,Yongfang Qian,Ying Wang
Due to their high porosity, large specific surface area, and structural similarity with the extracellular matrix (ECM), electrospun nanofiber membranes are often endowed with the antibacterial properties for biomedical applications. The purpose of this study was to synthesize nano-structured Sc2O3-MgO by doping Sc3+, calcining at 600 °C, and then loading it onto the PCL/PVP substrates with electrospinning technology with the aim of developing new efficient antibacterial nanofiber membranes for tissue engineering. A scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDS) were used to study the morphology of all formulations and analyze the types and contents of the elements, and an X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR) were used for further analysis. The experimental results showed that the PCL/PVP (SMCV-2.0) nanofibers loaded with 2.0 wt% Sc2O3-MgO were smooth and homogeneous with an average diameter of 252.6 nm; the antibacterial test indicated that a low load concentration of 2.0 wt% Sc2O3-MgO in PCL/PVP (SMCV-2.0) showed a 100% antibacterial rate againstEscherichia coli(E. coli).Keywords:nano-textured;Sc2O3-MgO;antibacterial;electrospinning
研究领域:
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2015
·
IF 2.605
Xuechen Huang,Hanxing Liu,Hua Hao,Shujun Zhang,Yue Sun,Wenqin Zhang,Lin Zhang,Minghe Cao
MgO-doped 0.97BaTiO 3 –0.03BiYO 3 (0.97BT–0.03BY) polycrystalline ceramics were prepared by the solid-state sintering method. Then the structural, dielectric and resistant properties were investigated as functions of MgO addition. Microstructure was studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS). The results show that Bi 3+ , Y 3+ and Mg 2+ ions exhibit nonuniform distribution behavior in BT–BY ceramics, demonstrating the existence of a “core–shell” structure, which plays important roles in the capacitance-temperature characteristics, where 0.97BT–0.03BY with the addition 2.2–2.8 at% MgO meets the Electronic Industries Association (EIA) X8R (−55 to 150 °C, ΔC / C 25 °C =±15% or less) specification. Moreover, the fine-grained samples with core–shell structure show much higher bulk resistance than the coarse-grained samples over the studied temperature range, which is attributed to the higher proportion of grain boundaries and the lower concentration of the effective acceptor.
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
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
·
2021
·Vol. 68
·期 10
·1897-1907
·
IF 1.967
Zhen Zhu,Yu-Teng Hwang,Hao-Chun Liang,Ren-Jang Wu
In this study, several Pd/MgO/BiVO 4 nanocomposites were prepared using the hydrothermal method and their effective photocatalyst activity for the photoreduction of CO 2 to CH 4 was investigated. The microstructure and photocatalytic behavior of the prepared photocatalysts were studied through X-ray diffraction, scanning electron microscopy, tunneling electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectrophotometry, Fourier-transform infrared spectroscopy, Brunauer–Emmett–Teller specific surface area, and photoluminescence spectroscopy. CH 4 yields of 5.9 and 9.4 μmol g −1 hr −1 were obtained using BiVO 4 and 25% MgO/BiVO 4 nanocomposites, respectively. The highest production rate of CH 4 was measured as 12.8 μmol g −1 hr −1 on overloading 0.3% Pd on 25% MgO/BiVO 4 . Pd/MgO/BiVO 4 exhibited excellent CO 2 photoreduction stability with negligible loss after five consecutive cycles. Finally, a possible mechanism of CO 2 photoreduction using Pd/MgO/BiVO 4 was proposed for understanding the synergistic effects. The results of the experiment revealed that Pd/MgO/BiVO 4 can be a promising photocatalyst in solar energy conversion and storage application and can achieve excellent CO 2 photoreduction performance.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2024
·
IF 1.8
Zhuoqun Han,Jia Liu,Weiwei Wang,Qingxuan Zhou,Zhicheng Zhao,Yongning Han,Yingying Wang,Yang Wang,Futian Liu,Ling Li
Si 3 N 4 ceramics with high mechanical properties and thermal conductivity, exhibiting fine and bimodal microstructure, were prepared by adjusting the Er 2 O 3 /MgO ratio and hot-pressing sintering at 1800°C for 4 h. The microstructure, grain distribution, lattice oxygen content, mechanical properties, and crack propagation process of the sintered bulk samples were systematically investigated. It was found that a low Er 2 O 3 /MgO ratio contributed to the densification of Si 3 N 4 ceramics, whereas a high Er 2 O 3 /MgO ratio favored the grain growth of Si 3 N 4 ceramics. In this research, the grain size distribution and average diameters as well as their impact on mechanical properties were examined. When the ratio of Er 2 O 3 /MgO was 3:1, Si 3 N 4 had a larger average diameter and higher thermal conductivity, but the mechanical properties were somewhat reduced. When the ratio of Er 2 O 3 /MgO was 2:2, the sample displayed enhanced mechanical performance, which can be explained by the formation of a bimodal structure. The research indicates that it is feasible to control the microstructure and optimize the mechanical properties of Si 3 N 4 ceramics by tailoring the sintering additives.
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
危险品化学品经营许可证（带存储）