CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Zhao Lu,Yan Wang,Xiaochuang Di,Runrun Cheng,Longqi Yang,Peihu Gao
In order to overcome the problems caused by electromagnetic pollution, the design and development of high-performance microwave absorbers is urgently required. In this work, a hierarchical ZnFe 2 O 4 @MnO 2 @RGO composite was successfully fabricated via a facile and rapid hydrothermal method . Its unique core-shell structure and synergistic effect between multiple components are beneficial for electromagnetic wave absorption. The morphology, elemental composition, microstructure and microwave absorption characteristics were systematically studied. With a filler loading of 20 wt%, the composite presents a minimum reflection loss (R Lmin ) of −46.7 dB and an effective absorption bandwidth (EAB) as wide as 5.2 GHz at a thickness of 2.5 mm. The superior absorption ability profits from a special microstructure, good impedance matching, multiple attenuation features, interfacial polarization, and the synergistic effect of dielectric and magnetic loss. Consequently, this work lays a foundation for the design of high-performance electromagnetic wave absorbers with multicomponent heterogeneous structures.
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
MOLECULES
·
2022
·Vol. 27
·期 15
·4863
·
IF 4.927
Shun Li,Zuquan Zheng,Zhicheng Zhao,Youling Wang,Yao Yao,Yong Liu,Jianming Zhang,Zuotai Zhang
CeO2nanoparticle-loaded MnO2nanoflowers, prepared by a hydrothermal method followed by an adsorption-calcination technique, were utilized for selective catalytic reduction (SCR) of NOxwith NH3at low temperatures. The effects of Ce/Mn ratio and thermal calcination temperature on the NH3–SCR activity of the CeO2-MnO2nanocomposites were studied comprehensively. The as-prepared CeO2-MnO2catalysts show high NOxreduction efficiency in the temperature range of 150–300 °C, with a complete NOxconversion at 200 °C for the optimal sample. The excellent NH3–SCR performance could be ascribed to high surface area, intimate contact, and strong synergistic interaction between CeO2nanoparticles and MnO2nanoflowers of the well-designed composite catalyst. The in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) characterizations evidence that the SCR reaction on the surface of the CeO2-MnO2nanocomposites mainly follows the Langmuir–Hinshelwood (L-H) mechanism. Our work provides useful guidance for the development of composite oxide-based low temperature NH3–SCR catalysts.Keywords:Mn-Ce mixed oxide;ion-adsorption;selective catalytic reduction;NOxconversion
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Siyao Zhang,Shiyou Yu,Xin Wang,Yipeng Zhang,Zhenge Yue,Chenchen Li,Yongqiang Ma
During beekeeping, the utilization of metronidazole (MNZ) for treating bee ailments leads to the MNZ residues in honey. Prolonged ingestion of honey with MNZ residues could pose potential health hazards to humans. Therefore, the development of a straightforward and efficient MNZ detection method is of utmost importance. ZnO, a non-toxic catalytic material, exhibits promising potential in electrochemical sensor design. The resulting g-C 3 N 4 /MnO 2 /ZnO composite was employed to craft an electrochemical sensor that facilitates swift MNZ quantification in honey. Comprehensive characterization of the synthesized composites was performed, and the electrochemical behavior of MNZ was explored using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It was found that the g-C 3 N 4 /MnO 2 /ZnO composite exhibits remarkable electrocatalytic capability, and the resulted sensor demonstrates good sensitivity. Within a range of 2–250 μM, MNZ's current value showed two linear relationships with its concentration, achieving the detection limit of 0.21 μM. When applied to honey samples, the g-C 3 N 4 /MnO 2 /ZnO/GCE sensor detected MNZ with recovery rates spanning 93.7% to 100.3% and relative standard deviations (RSD) under 3%. This attributed to heightened sensitivity, selectivity, repeatability and durability of the sensor. Furthermore, its effectiveness extends to the rapid assessment of MNZ content in actual honey, highlighting its practical utility in identifying MNZ residues in honey.
研究领域:
食品科学
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分析化学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Guangli Li,Yafeng Zhang,Yonghui Xia,Tianyu Wang,Yuan Jin
Excessive consumption of Sunset Yellow (SY) and Tartrazine (Tz) might cause adverse effects on human health. Hence, it is essential to develop a rapid and reliable technique for simultaneous determination of SY and Tz. Herein, an innovative voltammetric sensor was constructed for simultaneous determination of SY and Tz using multiwalled carbon nanotubes decorated dandelion-like α-MnO 2 microspheres (MnO 2 /MWCNTs). The physiochemical properties of MnO 2 /MWCNTs were studied by various microscopic, spectroscopic, and electrochemical techniques. Various parameters, including accumulation time, accumulation potential, loading volume, buffer pH, and scanning rate, were systematically explored in order to pursuit the higher peak current response. The MnO 2 /MWCNT effectively enlarged the electroactive surface area and expedited the electron transfer. As a result, the MnO 2 /MWCNT decorated glassy carbon electrode (GCE) displayed superior sensing performance for the electrooxidation of SY and Tz over a wide concentration range (0.06–10 μM), owing to the synergistic effect from dandelion-like α-MnO 2 microspheres and highly conductive MWCNTs. The detection limits were 0.005 and 0.01 μM for SY and Tz, respectively. In addition, the MnO 2 /MWCNT/GCE demonstrated strong anti-interfering capacity against potential interfering species, and highly reproducible electrode manufacture. The MnO 2 /MWCNT/GCE was successfully employed for the simultaneous and sensitive determination of SY and Tz in carbonate beverage with good recovery.
研究领域:
分析化学
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食品科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2019
·
IF 6.393
Xue Hu,Xidong Liu,Xiaodan Zhang,Haiyan Cao,Yuming Huang
By tuning the photoluminescence of alloy Cu/Ag nanoclusters (NCs) and thiamine (VB 1 ) simultaneously through MnO 2 nanowires, we report a simple and label-free ratiometric fluorescent platform for sensitively and selectively sensing of glutathione (GSH). Ag doping of Cu NCs significantly enhances the quantum yield (QY, about 2-fold enhancement), oxidation resistance to air, storage stability (60 days versus 1 day), photostability and salt stability of the resultant Cu/Ag NCs. Impressively, MnO 2 nanowires quench the fluorescence of Cu/Ag NCs, while they enhance the fluorescence of nonfluorescent VB 1 via oxidation reaction between VB 1 and dissolved oxygen to produce oxVB 1 as a nanozyme catalyst. Upon introduction of GSH as a target, the MnO 2 nanowires are reduced to Mn 2+ and lose their quenching capacity and oxidase-like activity, resulting in FL recovery of Cu/Ag NCs and fluorescent decrease of oxVB 1 . Hence, a ratiometric luminescence signal is obtained, providing a novel ratiometric fluorescent strategy for detecting GSH through target induced regulation of the catalytic activities and quenching ability of MnO 2 nanowires. The sensor exhibited a wide linear concentration range (10 nM to 70 μM) for GSH with a detection limit of 6.5 nM. The ratiometric sensor was successfully used for GSH detection in biological samples.
研究领域:
分析化学
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生物医学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 97
·94682-94686
·
IF 3.289
Li Liu,Jie Zhao,Wei-Hua Li,Xiao-Ying Zhang,Hui-Zhong Xu,Kai Li,Yan Kai,Li-Shui Sun,Chao-Qin Li,Fa-Qian Liu
An effective strategy to improve the conductivity of MnO2-based electrodes is to combine them with some conductive materials, such as metal or carbon-based materials. In this work, Ag nanoparticles decorated MnO2/Sulfonated Graphene composite with 3D macroporous structure (3D Ag–MnO2/SG) was synthesized and their performance as electrode material in supercapacitors was studied. The improved conductivity and the elaborate design of 3D porous structure allowed the 3D Ag–MnO2/SG electrode to possess enhanced electrochemical performance. For example, the electrochemical testing results demonstrated that the 3D Ag–MnO2/SG presents a capacitance of 537 F g−1 at 0.5 A g−1, which is much higher than that of MnO2 (∼172 F g−1). Moreover, the 3D Ag–MnO2/SG electrode delivers a higher capacity retention rate in high current density and smaller charge transfer resistance than that of MnO2, which is contributed by the synergistic effect from the Ag nanoparticles and the 3D porous SG.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2023
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IF 5.9
Shanyi Wang,Weihao Jin,Yujia Wu,Wanzhen Li,Yugui Tao,Jun Wang,Kai Yang,Weiwei Zhang,Lin Gui,Fei Ge
Drug-resistant bacterial infections pose a significant threat to global public health. Furthermore, the formation of biofilms makes traditional antibiotic treatments significantly less effective in killing multidrug-resistant (MDR) bacteria. In this work, we prepared a molybdenum disulfide (MoS2) nanosphere-based nanocomposite that utilized both photothermal therapy (PTT) and chemodynamic therapy (CDT) for effectively eradicating biofilms. A layer of manganese dioxide (MnO2) was adsorbed onto the surface of the MoS2 nanospheres by redox and electrostatic adsorption methods, and the resulting MoS2/MnO2 were loaded with 2,2′-azobis[2-(2-imidazolin-2-yl)propane]-dihydrochloride (AIPH) to form the MoS2/MnO2-AIPH nanocomposite (MMA). The microenvironment of biofilms is slightly acidic, lacks oxygen, and has a high concentration of glutathione (GSH). The MnO2 was capable of reacting with GSH to deplete it while also generating •OH radicals for CDT. In the presence of NIR light (808 nm), the temperature increase brought about by PTT further enhanced the CDT efficacy synergistically. The results showed that the photothermal conversion efficiency of the MMA was 40.5% at a concentration of 100 μg/mL, and the biofilm eradication rate of both MDR Escherichia coli and MDR Staphylococcus aureus was above 90%. The high bacterial inhibition rate (above 96%), as well as the excellent biosafety and biocompatibility of the MMA nanocomposite enabled it to effectively promote wound healing, which has significant implications in treating bacterial infections and promoting wound healing in clinical settings.
研究领域:
生物医学工程
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材料科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Qiuling Chen,Shun Wang,Baoji Miao,Qiuping Chen
The creation of a Z-scheme heterojunction is a sophisticated strategy to enhance photocatalytic efficiency. In our study, we synthesized an In 2 S 3 /MnO 2 /BiOCl dual Z-scheme heterostructure by growing BiOCl nanoplates on the sheets of In 2 S 3 nanoflowers, situated on the surface of MnO 2 nanowires. This synthesis involved a combination of hydrothermal and solution combustion methods. Experiments and density functional theory (DFT) calculations demonstrated that the In 2 S 3 /MnO 2 /BiOCl composite exhibited notable photo reduction performance and photocatalytic stability. This was attributed to the pivotal roles of BiOCl and MnO 2 in the composite, acting as auxiliaries to enhance the electronic structure and facilitate the adsorption/activation capacity of CO 2 and H 2 O. The yield rates of CO, CH 4 , and C 2 H 4 over In 2 S 3 /MnO 2 /BiOCl as the catalyst were 3.94, 5.5, and 3.64 times higher than those of pure In 2 S 3 , respectively. Photoelectrochemical analysis revealed that the dual Z-scheme heterostructure, with its oxygen vacancies and large surface area, enhanced CO 2 absorption and active sites on the nanoflower/nanowire intersurfaces. Consequently, the dual Z-scheme charge transfer pathway provided efficient channels for boosting electron transfer and charge separation, resulting in high C 2 H 4 , CH 4 , and CO yields of formed and exihibits an promising photoreduction rate of CO 2 to CO (51.2 µmol/g.h), CH 4 (42.4 µmol/g.h) and C 2 H 4 (63.2 µmol/g.h), respectively. DFT, in situ Diffuse reflectance infrared fourier transform spectroscopy, and temperature-programmed desorption tests were employed to verify the intermediates pathway. The study proposed a potential photocatalytic mechanism based on these findings.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2020
·Vol. 12
·期 47
·24196-24205
·
IF 6.895
Heng Zhang,Peigen Zhang,Long Pan,Wei He,Qi Qi,Zhuoheng Bao,Li Yang,Wei Zhang,Michel W. Barsoum,ZhengMing Sun
Lithium–sulfur (Li–S) batteries are regarded as potential next-generation energy storage systems due to their high theoretical energy densities. However, the dissolution of lithium polysulfides (LiPSs) upon cycling can result in severe capacity degradation. Achieving high rate capabilities with good cycling stability remains a huge obstacle for the practical implementation of Li–S batteries. Here we developed a novel, multifunctional, hierarchical structure by self-assembling core–shell MnO2 nanorods @ hollow porous carbon with 2D Ti3C2Tx nanosheets, labelled as MCT, as an efficient polysulfide mediator for Li–S cathodes. The integration of the polar MnO2 core and hollow porous carbon shell captures LiPSs two ways: physical confinement and chemisorption. The conductive Ti3C2Tx nanosheets construct a continuous and conductive network, which not only promotes charge transfer and ion diffusion but also boosts LiPS adsorption and conversion. Based on these merits, the MCT/S cathode delivers good rate capability (688 mA h g−1 at 2.0C) and outstanding long-term cyclability (0.044% capacity decay per cycle over 600 cycles at 2.0C).
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Jiangshan Gao,Huanhuan Wang,Yang Zhou,Zhiming Liu,Yan He
The combination of magnetic nanoparticles and transition metal oxides has attracted much attention in microwave absorption applications. Herein, the MnO 2 /Mn 3 O 4 @Ni-Co/graphite carbon (GC) nanocubes with porous structure and ultrathin nanosheets was constructed by self-template strategy and in-situ synthesis. The composites not only synergize the magnetic loss of magnetic Ni-Co nanoparticles with the dielectric losses of GC and MnO 2 /Mn 3 O 4 , but also enhance the multiple interface polarization and improve impedance matching. As a result, the MnO 2 /Mn 3 O 4 @Ni-Co/GC nanocubes present outstanding electromagnetic wave (EMW) absorption performances, in which a RL min of −26 dB at 6.4 GHz with a thickness of 4 mm and an effective absorption bandwidth covering from 5.3 GHz to 6.4 GHz are achieved. Meanwhile, the widest effective absorption bandwidth with the value of 3.7 GHz can be achieved at a matching thickness of 2.0 mm. More importantly, this work provides a new strategy for the synthesis of EMW absorbing materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Xiao Ge,Juntao Liu,Xiangyang Song,Guozhong Wang,Haimin Zhang,Yunxia Zhang,Huijun Zhao
The hierarchical flower-like iron containing γ-MnO 2 hollow microspheres assembled by ultrathin nanosheets have been successfully fabricated via a facile one-step co-precipitation route in the absence of additional templates or surfactants. Structural characterization show that iron element is uniformly incorporated into γ-MnO 2 framework, and no segregated iron oxide appears. The resulting iron containing MnO 2 hollow microspheres exhibit a noticeable enhanced performance for As(III) removal compared to that of the undoped counterparts, accompanied by 102.84 mg/g of the saturated removal capacity towards As(III). The excellent performance for the arsenic removal may be attributed to the unique structural characteristics of highly accessible surface and fully exposed active sites inherited from the hierarchical iron containing γ-MnO 2 samples. The co-existence of oxidation and adsorption is another key factor for the improvement of As(III) removal efficiency, in which manganese dioxide is mainly responsible for oxidizing As(III) to As(V) and ferrous species may serve to the adsorption of the generated As(V), as evidenced by X-ray photoelectron spectroscopy (XPS) analysis. Importantly, the composites exhibit an excellent regenerative ability over three cycles without a significant decrease in its removal efficiency towards As(III). Furthermore, the relatively large micrometer-scale particles can be easily separated by filtration, accompanied by fewer secondary contaminants risks than nanoparticles. Therefore, the fabricated hierarchical Fe-containing γ-MnO 2 hollow spheres in the present study will be an excellent candidate for the arsenic transformation and removal from the contaminated water based on the synergistic effects of effective oxidizing and adsorptive performance, good regeneration together with the convenient separation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2017
·
IF 4.95
Junhua Li,Jianbo Jiang,Mengqin Liu,Zhifeng Xu,Peihong Deng,Dong Qian,Chaoying Tong,Haobin Xie,Chunming Yang
Tailored designs/fabrications of hierarchical porous advanced electrode materials are of great importance for developing high-performance electrochemical sensors. Herein, we demonstrate a simple and low-cost in situ chemical approach for the facile synthesis of MnO 2 -embedded hierarchical porous carbon microspheres (MnO 2 /CM). By the characterizations of scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction and energy dispersive spectroscopy , we evidenced that the synthesized product were flower-like carbon microspheres (CM) assembled by the bent flakes with thickness of about several nanometers and MnO 2 nanorods were highly dispersed and successfully decorated on the CM layers, resulting in a rough surface and three-dimensional microstructure. The greatest benefit from the combined porous CM with MnO 2 nanorods is that the MnO 2 /CM modified electrode has the synergetic catalysis effect on the electro-oxidation of caffeic acid , leading to the remarkable increase in the electron transfer rate and significant decrease in the over-potential for the caffeic acid oxidation in contrast to the bare electrode and CM modified electrode . This implies that the prepared MnO 2 /CM can be employed as an enhanced electrocatalyst for the sensitive detection of caffeic acid. Under the optimum conditions, the anodic peak current of caffeic acid is linear with its concentration in the range of 0.01–15.00 μmol L −1 , and a detection limit of 2.7 nmol L −1 is achieved based on S/N = 3. The developed sensor shows good selectivity , sensitivity, reproducibility, and also excellent recovery in the detections of real samples, revealing the promising practicality of the sensor for the caffeic acid detection.
研究领域:
材料科学
·
分析化学
✓ 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）