CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Fei Li,Li Zhuang,Wenwei Zhan,Manxi Zhou,Gang Sui,Aosong Zhou,Gang Bai,Wei Xiao,Xiaoping Yang
ZnO decorated ZnFe 2 O 4 nanoparticles were synthesized and combined with reduced graphene oxide (rGO) to form ZnFe 2 O 4 @ZnO@rGO ternary hierarchical nanocomposites by a controllable method. The microstructure, morphology, and microwave absorption performance of the ZnFe 2 O 4 @ZnO@rGO nanocomposites were investigated in detail. The permittivity and permeability of the composites can be effectively regulated by controlling the content of ZnO and rGO to achieve a good impedance matching. Due to the synergistic effect of dielectric loss and magnetic loss, the ZnFe 2 O 4 @ZnO@rGO nanocomposites exhibited strong wave absorption and wide absorption bandwidth. The optimal reflection loss (RL) of the ZnFe 2 O 4 @ZnO@rGO nanocomposites reached −35.2 dB at 12.0 GHz with a thickness of 2.0 mm and the effective absorption bandwidth was 3.7 dB. The ZnFe 2 O 4 @ZnO@rGO hierarchical architecture produced lots of heterogeneous interfaces which made a significant contribution to the wave absorption performance. The combination of interfacial polarization, dipole polarization, and eddy current loss enhanced the microwave absorption capacity of the ZnFe 2 O 4 @ZnO@rGO system. This work provides a feasible approach for the design and preparation of wave absorption materials with tunable permittivity and permeability.
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Meiyu Yuan,Changxin Peng,Junjie Fu,Xuening Liu,Zihan Wang,Shiyu Xu,Sheng Cui
Accurate and convenient detection of nitrogen dioxide (NO 2 ) in the air, which is harmful to human health, is vital. However, it is difficult for many NO 2 detection devices to achieve high sensitivity at room temperature. In this work, we synthesized zeolite-imidazolate-frameworks-8 (ZIF-8) nanoparticles and zinc oxide/reduced graphene oxide (ZnO/rGO) aerogel by low-temperature synthesis and sol-gel method. The aerogel composite materials were investigated by X-ray diffractometer (XRD), scanning electron microscopy (SEM), Brunaue-Emmette-Teller (BET), and Raman spectroscopy . The gas-sensitive element prepared by the material with the mass ratio ZIF-8 to rGO is 5:1 possesses excellent selectivity and higher sensitivity (3.21) to 100 ppm NO 2 at room temperature. Reduced graphene oxide (rGO) provides more gas transmission and diffusion channels for improving sensitivity because of a three-dimensional porous structure. When NO 2 is exposed, electrons transfer into p-n heterostructure formed by rGO and ZnO composite to achieve the purpose of sense. In this study, the material preparation method is relatively simple and efficient, which is of profound significance to accurately detect the variation of NO 2 concentration in air at room temperature.
研究领域:
材料科学
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环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2020
·Vol. 26
·期 8
·3831-3840
·
IF 2.394
Pei Mengchun,Wu Yuandong,Qi Zhiqiang,Mei Dajiang
NiO/Fe 3 O 4 /rGO composite materials were successfully obtained via a solvothermal route and characterized by charge/discharge test, TEM, XRD, SEM, EIS, HRTEM, XPS, CV, etc. The results showed that the Fe 3 O 4 nanospheres have an average size around 150 nm, NiO is relatively larger (about 300 nm) and agglomerated by rod-shaped particles. The nanospheres of Fe 3 O 4 and rod-shaped NiO particles were distributed on the surface of reduced grapheme oxide. The BET specific surface and BJH desorption average pore diameter of NiO/Fe 3 O 4 /rGO are 497.26 m 2 g −1 and 1.23 nm, respectively, so it improves the contact area between electrode materials and electrolyte, make ion diffusion path shorter and facilitates ion insertion/desertion. Discharge capacity was 841 mAh g −1 at the first cycle and maintain 647 mAh g −1 after 200 cycles at the current density of 500 mA g −1 , and even at the current density of 1000 mA g −1 , the discharge capacity can keep 582 mAh g −1 after 200 cycles with a well Coulombic efficiency and retention. And electrochemical impedance of NiO/Fe 3 O 4 and NiO/Fe 3 O 4 /rGO is 110 Ω and 75 Ω, respectively, indicating that the material has a good ionic conductivity.
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
FOOD CHEMISTRY
·
2025
·
IF 9.8
Xishun Peng,Yiheng Yuan,Anjiang Lu,Cunwei Wang,Caizhen Zu,Haili Zhang,Zhongchen Bai
Glyphosate (Gly) residues in agricultural products have a serious health risk, so it is urgent to seek a sensitive and convenient method for recognizing Gly residues in food. In this study, we proposed an electrochemical surface-enhanced Raman spectroscopy (EC-SERS) sensor of polyaniline/reduced graphene oxide/Ag/Cu (PANI/RGO/Ag/Cu) film to detect Gly residues. The EC-SERS sensor of PANI/RGO/Ag/Cu film had a large specific surface area, which could increase the binding sites of cu 2+ /Gly clathrates for boosting specifically its SERS signal. Moreover, Ag/Cu nanoparticles on the surface of film could effectively increase the differential pulse voltammetry signal and SERS signal of Gly molecules. The limit of detection of EC-SERS sensor to Gly could reach 1.9 nM. In addition, the EC-SERS sensor we prepared could also sensitively identify Gly residues on fresh fruit peels. The PANI/RGO/Ag/Cu film we proposed in this paper has great potential for selective and accuracy detecting Gly residues in agricultural products.
研究领域:
食品科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Zihao Yin,Jingyun Chen,Zhenbo Qin,Yingjun Wang,Zhong Wu
We developed a layered composite with directional distributed reduced graphene oxide (RGO) in a copper matrix through a double-slot multi-step electrodeposition method, playing to the advantage of in-plane thermal conductivity of RGO. The resulting RGO/Cu composite has superior thermal conductivity up to 545 W m −1 K −1 (150% of copper), which was determined by the growth behavior of the RGO flake on the copper substrate through adjusting electrodeposition time. By analyzing the structure, distribution status and its relationship with thermal conductivity, three factors including of structural integrity of RGO, thermal conduction network and interfacial effect between RGO layers were proposed. With the increase of deposition time, the restoration of RGO lattice structure and the formation of a complete thermal conduction network both promoted the phonon transmission, which was beneficial to the improvement of thermal conductivity. The multi-layer stacking of RGO, however, could generate the interlayer interfacial effects, resulting in the phonon scattering and unfavorable to the thermal conductivity. Therefore, proper adjustment of RGO deposition time resulted in excellent thermal conductivity of RGO/Cu composite, meeting the demands for the heat dissipation performance of the instrument.
研究领域:
材料科学
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热工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 27
·16592-16599
·
IF 3.361
Jiaqi Geng,Yuanli Men,Chen Liu,Xiang Ge,Caideng Yuan
In this study, we report a simple method to improve the thermal conductivity of epoxy resin by using new magnetic composites as fillers. The rGO@Fe3O4 nanocomposite has been prepared by a solvothermal method, and its morphology and chemical structure were characterized and analyzed by various characterization methods. Afterwards, the rGO@Fe3O4/EP composite material was obtained in an external magnetic field, in which the rGO@Fe3O4 is uniformly dispersed in the epoxy resin matrix, arranged along the direction of the magnetic field. In addition, the orientation of rGO@Fe3O4 increases with the magnetic field intensity. After doping 30% (wt) rGO@Fe3O4 into epoxy resin and curing under a 500 Gs magnetic field, the rGO@Fe3O4/EP composite material is anisotropic and has a higher thermal conductivity (increased by 196.60%) parallel to the direction of the magnetic field compared to a pure ring oxygen resin.
研究领域:
材料科学
·
热传导工程
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Wenyan Du,Yuanke Wu,Tingting Yang,Bingshu Guo,Dingyu Liu,Shu-Juan Bao,Maowen Xu
Developing high energy density room-temperature sodium sulfur (RT Na-S) batteries relies on the design of delicate structure that can be efficiently injected sulfur and enhance the cycle life of electrode active material. Herein, a three dimensional (3D) hierarchical cathode substrate with VO 2 nanoflowers as catalyst in situ grown on reduced graphene oxide (rGO) for sulfur cathodes are designed and prepared. In this novel structure, the electronic conductivity of sulfur cathode can be greatly improved due to the high electrical conductivity of rGO substrate. More importantly, the catalytic effect of VO 2 accelerates the conversion long-chain NaPSs to Na 2 S 2 /Na 2 S, and enhances the cycle capability, which can be validated by experimental data. As a result, the as-obtained rGO/VO 2 /S composites achieves an initial reversible capacity of 876.4 mA h g −1 at 0.2C. Moreover, the capacity of 156.1 mA h g −1 is demonstrated after long-cycling term of 1000 cycles at 2C and high cycle stability of only 0.07% capacity decay per cycle is exhibited.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 5
·917
·
IF 5.3
Donglin Li,Junfeng Lu,Xuanji Zhang,Dingfeng Jin,Hongxiao Jin
Nanoscale heterostructured zinc oxide/reduced graphene oxide (ZnO/rGO) materials with p–n heterojunctions exhibit excellent low temperature NO2gas sensing performance, but their doping ratio modulated sensing properties remain poorly understood. Herein, ZnO nanoparticles were loaded with 0.1~4% rGO by a facile hydrothermal method and evaluated as NO2gas chemiresistor. We have the following key findings. First, ZnO/rGO manifests doping ratio-dependent sensing type switching. Increasing the rGO concentration changes the type of ZnO/rGO conductivity from n-type (<0.6% rGO) to mixed n/p -type (0.6~1.4% rGO) and finally to p-type (>1.4% rGO). Second, interestingly, different sensing regions exhibit different sensing characteristics. In the n-type NO2gas sensing region, all the sensors exhibit the maximum gas response at the optimum working temperature. Among them, the sensor that shows the maximum gas response exhibits a minimum optimum working temperature. In the mixed n/p-type region, the material displays abnormal reversal from n- to p-type sensing transitions as a function of the doping ratio, NO2concentration and working temperature. In the p-type gas sensing region, the response decreases with increasing rGO ratio and working temperature. Third, we derive a conduction path model that shows how the sensing type switches in ZnO/rGO. We also find that p–n heterojunction ratio (np–n/nrGO) plays a key role in the optimal response condition. The model is supported by UV-vis experimental data. The approach presented in this work can be extended to other p–n heterostructures and the insights will benefit the design of more efficient chemiresistive gas sensors.Keywords:p–n junctions;ZnO;reduced graphene oxide;rGO;NO2sensing
研究领域:
材料科学
·
传感器技术
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纳米科技
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 11
·5749-5759
·
IF 2.936
Pingfan Xu,Siyi Huang,Yuancai Lv,Yi Chen,Minghua Liu,Haojun Fan
To solve the problem of contamination of hexavalent chromium (Cr(VI)), visible-light-driven graphene-based ternary metal chalcogenide nanosheets (rGO/SnIn4S8) were synthesized via a one-pot surfactant-assisted hydrothermal method for the photoreduction of Cr(VI). Characterizations demonstrated that SnIn4S8 nanosheets were uniformly distributed on the surface of rGO and the as-synthesized nanosheets exhibited excellent photocatalytic activity under visible light. In addition, the effects of pH, concentration of critic acid, holes and electron scavengers on the reduction of Cr(VI) were systematically investigated. It was found that 50 mg L−1 of Cr(VI) could be completely removed within 30 min at pH 2 when citric acid served as a hole scavenger. Kinetic studies showed that the photocatalytic reduction of Cr(VI) processes obeyed the pseudo first order model. Further study indicated that the Cr(III) species was immediately adsorbed onto the surface of the rGO/SnIn4S8 nanosheets after photocatalytic reduction of Cr(VI). Additionally, recycling results suggested that rGO/SnIn4S8 nanosheets possessed high recycle ability and stability after repeated use (5 times). This effective and promising work might provide a new strategy for the photoreduction of Cr(VI) and complete removal of chromium from effluent through the novel photocatalyst rGO/SnIn4S8.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2019
·Vol. 140
·期 4
·1759-1767
·
IF 2.471
Zhang Jiankan,Zhao Fengqi,Yang Yanjing,Yan Qilong,Zhang Ming,Ma Wenzhe
Fe 3 O 4 /reduced graphene oxide (Fe 3 O 4 /rGO) nanocomposite has been successfully fabricated using a modified interface solvothermal method and characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. In the preparation procedure, graphene oxide was reduced and ultrafine Fe 3 O 4 nanoparticles (NPs) were uniformly loaded on reduced graphene oxide (rGO) carrier. Scanning electron microscope, transmission electron microscope images and Brunauer–Emmett–Teller specific surface area revealed that the aggregation of Fe 3 O 4 NPs was greatly reduced by introducing rGO as a substrate. The average size of the Fe 3 O 4 NPs anchored on the graphene sheets was 100 nm, which is much smaller than 1-μm bare Fe 3 O 4 . The DSC results showed that Fe 3 O 4 /rGO nanocomposite reduces the first decomposition temperature of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) by 44.9 °C and decreases the apparent activation energy of TKX-50 by 26.2 kJ mol −1 , which exhibits higher catalytic performance than its individual components and their physical mixture (hybrid). Hence, Fe 3 O 4 /rGO nanocomposite can be a promising additive for insensitive solid propellants based on TKX-50.
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
·
2020
·Vol. 13
·期 4
·933
·
IF 3.057
Yuexuan Li,Yugang Duan,Chengmeng Wang
Graphene has been regarded as one of the most promising two-dimensional nanomaterials. Even so, graphene was still faced with several key issues such as impedance mismatching and narrow bandwidth, which have hindered the practical applications of graphene-based nanocomposites in the field of microwave absorption materials. Herein, a series of Si-modified rGO@Fe3O4composites were investigated and fabricated by a simple method. On one hand, the degree of defects in graphene carbon could be tuned by different silane coupling reagents, which were beneficial to enhancing the dielectric loss. On the other hand, the spherical Fe3O4nanoparticles provided the magnetic loss resonance, which contributed to controlling the impedance matching. Subsequently, the electromagnetic absorption (EMA) properties of Si-modified rGO@Fe3O4composites with poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) were investigated in this work. As a result, the Si(2)-rGO@Fe3O4/PVDF-co-HFP composite exhibited the excellent EMA performance in the range of 2–18 GHz. The maximum reflection loss (RLmax) reached −32.1 dB at 3.68 GHz at the thickness of 7 mm and the effective absorption frequency bandwidth for reflection loss (RL) below −10 dB was 4.8 GHz at the thickness of 2 mm. Furthermore, the enhanced absorption mechanism revealed that the high-efficiency absorption performance of Si(2)-rGO@Fe3O4/PVDF-co-HFP composite was attributed to the interference absorption (quarter-wave matching model) and the synergistic effects between Si(2)-rGO@Fe3O4and PVDF-co-HFP. This work provides a potential strategy for the fabrication of the high-performance EMA materials.Keywords:absorbing materials;Si-modified rGO@Fe3O4/PVDF-co-HFP composites;dielectric loss;magnetic loss;electromagnetic properties
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Shiyao Yan,Shiping Shao,Yunxiang Tang,Xin Zhang,Chan Guo,Luxue Wang,Jiurong Liu,Lili Wu,Fenglong Wang
Aerogel-based composites, renowned for their three-dimensional (3D) network architecture, are gaining increasing attention as lightweight electromagnetic (EM) wave absorbers. However, attaining high reflection loss, broad effective absorption bandwidth (EAB), and ultrathin thickness concurrently presents a formidable challenge, owing to the stringent demands for precise structural regulation and incorporation of magnetic/dielectric multicomponents with synergistic loss mechanisms within the 3D networks. In this study, we successfully synthesized a 3D hierarchical porous Fe3O4/MoS2/rGO/Ti3C2Tx MXene (FMGM) composite aerogel via directional freezing and subsequent heat treatment processes. Owing to their ingenious structure and multicomponent design, the FMGM aerogels, featured with abundant heterogeneous interface structure and magnetic/dielectric synergism, show exceptional impedance matching characteristics and diverse EM wave absorption mechanisms. After optimization, the prepared ultralight (6.4 mg cm–3) FMGM-2 aerogel exhibits outstanding EM wave absorption performance, achieving a minimal reflection loss of −66.92 dB at a thickness of 3.61 mm and an EAB of 6.08 GHz corresponding to the thickness of 2.3 mm, outperforming most of the previously reported aerogel-based absorbing materials. This research presents an effective strategy for fabricating lightweight, ultrathin, highly efficient, and broad band EM wave absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）