ACS Sustainable Chemistry & Engineering
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2019
·
IF 6.97
Lin Long,Erqi Yang,Xiaosi Qi,Ren Xie,Zhong-chen Bai,Shuijie Qin,Chaoyong Deng,Wei Zhong
Lots of research have focused on the core/shell structure nanocomposites owing to their synergistic effect that were considered as the most promising high-performance microwave absorbers (MAs). However, the excellent comprehensive properties of MAs are still in urgent need. Herein, positive and reverse core/shell structure CoxFe3–xO4/MoS2 (x = 1.5, 0.75 and 0.5) and MoS2/CoxFe3–xO4 (x = 0.5) nanocomposites were elaborately produced through an inexpensive two-step hydrothermal process. It was found that the CoxFe3–xO4/MoS2 samples exhibited a much smaller optimal reflection loss (RLopt) value and a broader frequency bandwidth (fb) with the lower value of matching thickness (dm) when the CoxFe3–xO4/MoS2 loadings were raised to 60 from 30 wt %. With the x value decreasing from 1.5 to 0.5, the obtained CoxFe3–xO4/MoS2 samples displayed a much smaller RLopt value with a thinner dm and a much larger fb value with the thin dm (∼2 mm). The sample consisting of 60 wt % CoxFe3–xO4/MoS2 (x = 0.5) exhibited an RLopt value of −66.83 dB with the dm of merely 1.57 mm, and its corresponding fb value could reach 6.64 GHz with the dm of 2.02 mm. Moreover, compared with the MoS2/CoxFe3–xO4 (x = 0.5) sample, the CoxFe3–xO4/MoS2 (x = 0.5) sample displayed evidently better microwave absorbing comprehensive performances in terms of low RLopt value, large fb value, and high chemical stability. Generally, the obtained results demonstrated that the designed CoxFe3–xO4/MoS2 nanocomposites could act as MAs with outstanding comprehensive properties.
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2019
·Vol. 21
·期 14
·2310-2319
·
IF 3.382
Yanlin Li,Xuegang Lu,Sen Yang,Wenyuan Duan,Yin Zhang,Chao Zhou,Kaili Li,Yanjun Zhang,Qian Shi
Monodisperse CoxFe3–xO4 colloidal particles with uniform size and tunable composition have been prepared using a one-step hydrothermal method. Magnetic measurements reveal the typical ferromagnetic nature of the material with a saturation magnetization (Ms) of up to 75.6 emg g−1 and a coercivity (Hc) of 810 Oe at room temperature. The synthesized colloidal particles can be highly dispersed in aqueous solution and show quick magnetic response. Under the induction of an external magnetic field, the colloidal particles in suspension will be assembled into a colloidal array and selectively reflect visible light so that bright structural colors are generated throughout the visible wavelength range. This finding reveals that in addition to traditional superparamagnetic colloidal particles (such as Fe3O4 and MFe2O4 (M = Zn, Mg, Mn, and Ni)), hard magnetic CoxFe3–xO4 with relatively high coercivity can also be used as a candidate material for constructing magnetically responsive colloidal photonic crystals with potential applications in color displays, biological detection and anti-counterfeiting technology.
研究领域:
材料科学
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光学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 34
·11936-11949
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IF 7.059
Mei Wu,Abdou Karim Darboe,Xiaosi Qi,Ren Xie,Shuijie Qin,Chaoyong Deng,Guanglei Wu,Wei Zhong
It is well-known that suitable optimization of electromagnetic parameters is a feature to achieve outstanding electromagnetic wave absorption performances (EMWAPs). Accordingly, an effective way to develop high-performance microwave absorbers is to construct dielectric–magnetic core/shell structure nanocomposites with a controllable microstructure and composition parameters. Herein, we propose a simple route to synthesize core/shell structure nanocomposites consisting of carbon nanotubes (CNTs) as the core and magnetic nanoparticles as the shell via a one-step hydrothermal method. By adjusting the experimental parameters, core/shell structure CNTs/CoxFe3−xO4 nanocomposites with different morphologies, contents of CNTs, Co : Fe molar ratios and types of CNTs were selectively synthesized. Also, the electromagnetic properties and EMWAPs of the obtained samples were highly dependent on their microstructure and composition parameters. Thus, by optimizing these parameters, the designed nanocomposites simultaneously exhibited very small values of minimum reflection loss and broad absorption bandwidth with very thin matching thicknesses. Additionally, the outstanding comprehensive EMWAPs of samples were proven to be attributed to their improved impedance matching, attenuation loss characteristics, dielectric loss abilities and excellent synergetic effect. Generally, considering the simple process, environment-friendly, low cost, controllable production and high stability of the nanocomposites, our findings provide an effective way to optimize electromagnetic properties and design high-performance microwave absorbers.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 67
·35500-35504
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IF 3.708
Wenshu Yang,Jinhui Hao,Zhe Zhang,Baoping Lu,Bailin Zhang,Jilin Tang
A facile approach was proposed for the synthesis of hierarchical CoxFe3−xO4 nanocubes (CF nanocubes), using Prussian Blue (PB) as precursor. The method consists of the synthesis of hierarchical cobalt–iron Prussian blue analogues (PBAs) through the reaction of PB nanocubes with CoCl2 in a water bath and subsequently calcining the corresponding PBA precursor. The obtained CF nanocubes were characterized using transmission electron microscopy, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and N2 adsorption–desorption isotherm measurements. It is found that the hierarchical CF nanocubes have a large specific surface area (108 m2 g−1). Considering the hierarchical structure and the doping of Co in Fe3O4 are beneficial for the catalytic activity of the catalyst, an efficient and simple colorimetric biosensor for H2O2 and glucose was fabricated using CF nanocubes as a peroxidase mimetic. The good catalytic activity and low-cost make the hierarchical CF nanocubes a useful biocatalyst for a wide range of potential applications in medicine and biotechnology.
研究领域:
生物传感
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材料科学
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医学诊断
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2019
·
IF 4.175
Mei Wu,Xiaosi Qi,Ren Xie,Zhongchen Bai,Shuijie Qin,Wei Zhong,Chaoyong Deng
By regulating the addition of iron source, different magnetic contents and Co:Fe molar ratios of graphene oxide/carbon nanotubes/Co x Fe 3- x O 4 (GO/CNTs/Co x Fe 3- x O 4 ) ( x = 0.6, 0.43 and 0.375) ternary nanocomposites (NCs) could be selectively synthesized by one-step hydrothermal method . The FE-SEM and TEM investigations indicated that the paper-like GO, CNTs and Co x Fe 3- x O 4 nanoparticles were well bound together to form the good three dimensional hierarchical networks, which could effectively provide more interface contacts. Among these obtained samples, the as-prepared GO/CNTs/Co x Fe 3- x O 4 ( x = 0.375) ternary NCs displayed superior electromagnetic wave (EMW) absorption capabilities in terms of the optimal reflection loss value of −71.3 dB and the absorption bandwidth of 2.52 GHz. And the enhanced EMW absorption capabilities of GO/CNTs/Co x Fe 3- x O 4 ( x = 0.375) ternary NCs were analyzed in details. Therefore, a simple route was proposed to produce three dimensional hierarchical networks of GO/CNTs based NCs for simultaneous constructing more interfacial polarizations, dielectric and magnetic loss mechanisms, which was demonstrated to effectively optimize the EMW absorption performances and could be applied to design high performance EMW absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Shu Li,Shaoli Guo,Guoxiang Chen,Yan Cui,Hangfan Yang,Jie Qiu,Zelin Wang,Minghan Dai,Shuai Liu
Substitution can cause changes in electromagnetic parameters thereby affecting the electromagnetic wave (EMW) absorption performance of the material. We inferred that the fundamental reason for the performance improvement is the transitions in the absorption mechanism, which is caused by the change in electronic structure that originated from the substitution. To confirm this, we prepared Co x Fe 3 − x O 4 (0 ≤ x ≤ 1) hollow microspheres and investigated its absorption performance in 2–18 GHz. Subsequently, a series of theoretical studies were carried out that focusing on the impact of increasing Co 2+ substitution on the electrical and magnetic loss mechanisms, as well as the inherent relationship between the substitution and the absorption performance. The result indicates that in terms of dielectric loss, an increase in Co 2+ substitution can induce a transition from conductivity loss to polarization loss by increasing the number of holes and strengthening the electron localization. Meanwhile, substitution results in a transformation from the eddy current loss to a magnetic resonance mode, and leads to an increase in magnetocrystalline anisotropy simultaneously, enhancing the magnetic loss ability. As a result, the transformation of electrical and magnetic loss mechanisms ultimately leads to an overall improvement in EMW absorption performance of Co x Fe 3 − x O 4 , and CoFe 2 O 4 hollow microsphere consequently realizes an extremely high attenuation performance of −72.3 dB at 2.67 mm. This work provides a deeper understanding of the intrinsic relationship between the macroscopic absorption performance of ferrite and its microscopic electronic structure, which can guide the synthesis of efficient ferrite absorbers.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2026
·
IF 6.7
Xiuzhou Lin,Long He,Lan Luo,Qiaoling Yang,Baojie Dou,Xinmiao Jiang,Yan Wang,Xinyue Liang
Hollow Co x Fe 3-x O 4 nanocontainers were loaded with SDBS and sealed by KH-560. • Nanocontainers participated in MAO growth and regulated discharge defects. • The specific wear rate of MAO-1 decreased by 95.8% compared with MAO-0. • MAO-1 showed the best corrosion resistance with superior electrochemical properties. • SVET confirmed corrosion-responsive inhibitor release and self-healing protection. The intrinsic porosity and microcracks inherent to micro-arc oxidation (MAO) coatings create preferential diffusion paths for corrosive species, thereby limiting the long-term corrosion protection of magnesium alloys. In this work, hollow mesoporous Co x Fe 3-x O 4 nanocontainers were synthesized via a cetyltrimethylammonium bromide (CTAB) assisted solvothermal method, loaded with sodium dodecylbenzenesulfonate (SDBS) as a corrosion inhibitor, sealed with KH-560 silane coupling agent, and subsequently incorporated into MAO coatings on AZ31B magnesium alloy. The nanocontainers participated in coating formation through pore filling and co-solidification with molten oxides. Moderate addition refined discharge pores and improved coating integrity, whereas excessive addition caused particle agglomeration and inhomogeneity. At the optimal concentration of 1 g·L -1 , MAO-1 exhibited the greatest coating thickness (37.96 μm). MAO-1 exhibited the highest coating resistance ( R c = 2.40×10 7 Ω·cm 2 ) and charge-transfer resistance ( R ct =1.77×10 6 Ω·cm 2 ), together with the lowest corrosion current density (2.85×10 -9 A·cm -2 ). Its specific wear rate was reduced to 2.56×10 −6 mm 3 ·N -1 ·m -1 , which is 95.8% lower than that of MAO-0. Scanning vibrating electrode technique (SVET) measurements further confirmed corrosion-responsive self-healing behavior in MAO-1: after 12 h of immersion, the maximum local potential-difference signal decreased from 0.0105 to 0.0042 mV, representing a 66.1% reduction compared to MAO-0. The progressive attenuation of local electrochemical activity indicates that the release, migration, and interfacial adsorption of SDBS effectively suppress localized anodic dissolution and partially restore protection at damaged regions. Overall, the Co x Fe 3-x O 4 @SDBS@KH-560 nanocontainers synergistically combine barrier reinforcement with inhibitor-mediated active protection, thereby enhancing the corrosion resistance, wear resistance, and self-healing capability of the MAO coating.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）