DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 41
·14767-14773
·
IF 4.099
Sisi Dai,Bin Quan,Baoshan Zhang,Xiaohui Liang,Guangbin Ji
In this work, novel one-dimensional (1D) Mo2C/Co@C nanorods (MCRs), using a metal–organic framework (zeolitic imidazolate framework; ZIF-67) as the coating layer to form multi-interfaces, were formed via a facile hard template method. Compared with previous works relating to porous-carbon-based Mo2C nanocomposites, the well-designed MCRs in this study possess a double attenuation mechanism due to the existence of the dielectric materials Mo2C and remaining carbon (RC) and the magnetic compound Co. Thanks to a new design and the multiple useful compounds, the as-prepared MCRs have the features of demonstrating multi-interfacial polarization, a large surface area and highly isotropic dissipation. Hence, the samples not only inherit the excellent microwave absorbing abilities of Mo2C but they also have a broadened effective bandwidth. For example, the minimum reflection loss (RL) value of MCRs with 35% sample loading could reach −47.98 dB. More importantly, RL values of less than −10 dB can be observed from 11.08 to 17.08 GHz (an effective bandwidth of 6.0 GHz) with a matching thickness of 1.6 mm, which is much better than previous work involving porous-carbon-based Mo2C nanocomposites. Firstly, we have reasonably redesigned the samples to have good absorbing properties for practical applications. Secondly, we have paved a highly efficient and universal way to synthesize 1D microwave absorbers with multiple valuable interfaces.
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
FUEL
·
2016
·
IF 3.611
Panpan Yang,Qineng Xia,Xiaohui Liu,Yanqin Wang
Catalytic transfer hydrogenation/hydrogenolysis of 5-hydroxymethylfurfural (HMF) to valuable chemicals, 2,5-dimethylfuran (DMF), is realized over a carbon supported nickel-cobalt catalyst with formic acid as hydrogen donor. The highest DMF yield, 90.0%, is achieved at 210 °C under self-generated pressure. A reaction route involving 5-methylfurfural (5-MF) instead of 2,5-bis(hydromethyl)furan (BHMF) as an intermediate has been investigated, which is different from that when H 2 is used as hydrogen source in previous reports. The influence of the amount of formic acid is investigated on the conversion of HMF and the yield of DMF. The effectiveness of this strategy has also been used for the conversion of furfural to 2-methylfuran, another valuable chemicals.
研究领域:
催化
·
化学工程
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Huixian Zhou,Yiqing Zeng,Zexian Low,Feng Zhang,Zhaoxiang Zhong,Weihong Xing
Developing cost-effective and high-efficient air purification materials for enhancing the indoor air quality has been an ongoing concern. Herein, MnO 2 /Co–C catalyst layers were wrapped on SiO 2 nanofiber by a combination of thermal pyrolysis and redox reaction method to prepare catalytic membranes (MCCS-x) for the efficient purification of indoor PM and HCHO. The core-dual-shell structure maintains the pore structure of the membrane, providing high gas permeability of 670 m 3 ·m −2 ·h −1 ·kPa −1 . Owing to the introduction of MnO 2 /Co–C enhanced the capture of PM, the optimized MCCS-2 exhibits high filtration efficiency of PM 0.3 and PM 2.5 (99.60% and 99.99%) with a low pressure drop (<80 Pa). In addition, MCCS-2 achieves 100% HCHO removal efficiency at room temperature due to its large specific surface area, high redox property and abundant Mn 4+ and oxygen species. The appropriate proportion of Mn/Co bimetallic sites synergy inhibits the formation of formate and carbonate intermediate species, thus MCCS-2 possesses excellent long-term catalytic stability than contrast sample (MCCS-3 and MS). This work demonstrates a new approach for the fabrication of high-performance catalytic membrane materials for indoor air purification.
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
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Shanxin Li,Zhiqi Zhai,Yijing Sun,Sichen Guo,Ting Peng,Hongying Yu,Xuzhou Jiang
The development of stealth materials with both efficient corrosion resistance and low-frequency microwave absorption is highly necessary. In this work, neural-structured Co@C/MWCNTs nanocomposites were successfully synthesized through a facile co-precipitation method, followed by a subsequent pyrolysis process. By adjusting the pyrolysis temperature, the pore structure, crystallinity, degree of graphitization, and electromagnetic parameters of the material were optimized. This optimization achieved a multi-mechanism synergistic effect in the low-frequency region (C-band), including impedance matching, dielectric loss, conductive loss, and magnetic loss. The results indicated that NCN-700 achieved a minimum reflection loss ( RL min ) of −64.31 dB at 4.88 GHz. Additionally, the neural-structured Co@C/MWCNTs nanocomposites exhibited significant effectiveness in low-frequency radar stealth applications, while also displaying superior corrosion resistance, self-corrosion potential ( E corr = 0.52 V), and self-corrosion current density ( I corr = 2.58 × 10 −6 A/cm 2 ). These findings suggest the promising potential for neural-structured Co@C/MWCNTs nanocomposites in applications related to low-frequency microwave absorption and corrosion protection.
研究领域:
材料科学
·
电磁学
·
防腐蚀工程
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2019
·
IF 5.439
Qing-Lu Song,Yun-Peng Zhao,Fa-Peng Wu,Guo-Sheng Li,Xing Fan,Rui-Yu Wang,Jing-Pei Cao,Xian-Yong Wei
Low aromaticity and a large number of oxygen-bridged bonds among the aromatic structural units of lignin make it possible to obtain chemicals directly. A novel Co/ [email protected] catalyst with high activity towards hydrogenolysis of lignin-derived aryl ethers was synthesized according to the pyrolysis process of a predesigned ZIF-67. According to the results of characterization by powder X-ray diffraction (XRD), N 2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), Co was reduced by the carbonized organic linker of ZIF-67, and N was doped into the carbon skeleton of the catalyst. The effects of holding time, temperature, and initial H 2 pressure on the catalytic performance of Co/ [email protected] were evaluated in the selective hydrogenolysis of benzyl phenyl ether (BPE). BPE was completely converted and the selectivity of monomer reached to 98.2% under optimized reaction conditions. The C alk -O bond in BPE was first dissociated to form toluene and phenol, and then phenol was rapidly hydrogenated to form cyclohexanol. Furthermore, the Co/ [email protected] catalyst shows high activity for hydroprocessing and selective cleavage of other lignin-derived aryl ethers, including phenylethyl phenyl, diphenyl ether, dibenzyl ether, dinaphthalene ether, guaiacol, anisole and veratrole.
研究领域:
催化
·
化学工程
·
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2022
·
IF 11.307
Zhe Zou,Mingqiang Ning,Zhenkuang Lei,Xueheng Zhuang,Guoguo Tan,Jianhua Hou,Hui Xu,Qikui Man,Jingbo Li,Run-Wei Li
Ti 3 C 2 T x is considered a candidate for high-efficiency microwave absorption materials due to its adjustable electrical conductivity , low density and high specific surface area in recent years. However, the single absorption mechanism could not meet the practical requirements as the functional microwave absorbers. Herein, 0D/1D/2D architectures of Co@C/MXene with 0D Co nanoparticles , 1D carbon nanotubes (CNTs) and 2D Ti 3 C 2 T x MXene nanosheets were rationally fabricated to enhance the microwave attenuation performance, in which Co@CNTs were in situ grown on Ti 3 C 2 T x MXene nanosheets . By changing the amount of Ti 3 C 2 T x MXene to optimize the impedance matching properties, the Co@C/M − 10 absorber exhibits excellent microwave attenuation performance with a minimum reflection loss of −50.5 dB at 5.9 GHz under a thickness of 4.0 mm. Meanwhile, the maximum effective absorption bandwidth (<−10 dB) of Co@C/M − 10 absorber can reach 5.8 GHz under 2.0 mm. The remarkable absorption performance can be ascribed to the synergistic effects of interface polarizations and magnetic loss. Moreover, the radar cross section (RCS) simulation was also performed via CST. Under the incident angle of 0°, the RCS reduction value of Co@C/M − 10 can reach 33.5 dBm 2 . This work provides a strategy for synthesizing MXene-based composite materials with tunable electromagnetic attenuation and wide absorption bandwidth performance .
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
Food Analytical Methods
·
2019
·Vol. 13
·期 3
·617-628
·
IF 2.413
Xiu Yi,Luo Ruiping,Han Baoqing,Liu Lu,Wang Hongsu
In this study, a cobalt-based mesoporous carbon material (Co@C) was prepared by self-assembly method and impregnation method, and carboxyl functionalization was carried out to obtain COOH-Co@C. Then, the penicillinase (Pen X) was immobilized on the carrier material by covalent binding. The methylene blue was electropolymerized onto the glassy carbon electrode, and then the immobilized enzyme material was modified onto the modified electrode to prepare a biosensor. After optimization of experimental conditions, the differential pulse method was used to detect penicillin sodium (Pen G) as an antibiotic model. Notably, measurement was performed without any pH redox probe, and a low limit of detection was obtained. The results showed that when the concentration of Pen G was 0.1–10 ng mL −1 , the corresponding current and concentration of the sensor showed a good linear relationship. The linear equation is y = 0.3881x + 17.20 ( r 2 = 0.9974); when the concentration range is 10–100 ng mL −1 , the linear equation is y = 0.1170x + 19.73 ( r 2 = 0.9959). The limit of detection is 0.64 ng mL −1 . The sensor is not only simple to prepare but also has high sensitivity and accurate detection. Finally, using the spike method, the actual sample detection was successfully realized.
研究领域:
分析化学
·
食品科学
·
环境监测
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Jinchuan Chen,Weiwei Lei,Chi Huang,Jiajia Wang,Yunxiang Zhang,Zhili Liu,Zhicai Xu,Kan Wang,Shuaiyi Guo
Coating carbon materials on the surface of magnetic metal is an effective strategy to obtain lightweight high performance anticorrosive absorbers. Herein, the structure of the dense anticorrosive shell (Co/C porous layer) coated on the surface of the magnetic core (Flaky carbonyl iron, FCI) was successfully constructed. And the electromagnetic parameters of the composites can be precisely adjusted by controlling the mass reaction ratio of polydopamine/sodium dodecyl benzene sulfonate modified Co/C composites (Co/C@PDA-SDBS) and polydopamine/polyethyleneimine modified FCI (FCI@PDA-PEI). When the reaction ratio was 4:6 (FCI@Co/C-4/6), the sample exhibited excellent microwave absorption performance with suitable impedance matching and strong attenuation ability. The minimum reflection loss ( RL min ) value reached − 72.6 dB at 14.8 GHz and the maximum effective absorption bandwidth (EAB) covered the Ku band (11.8–18 GHz) with a thickness of only 1.5 mm. Besides, the dense Co/C layer with effective isolation of FCI@Co/C-4/6 also represented the excellent corrosion resistance for its higher E corr (−0.193 V) and lower I corr (0.33 μA/cm 2 ). Therefore, our research provides a novel approach for reducing the application thickness of FCI and paves the way for commercial application of lightweight high performance anticorrosive microwave absorbents.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Electronic Materials
·
2019
·
IF 0
Ting Huang,Zhengchen Wu,Jiawei Lin,Qi Yu,Donggui Tan,Lei Li
The hierarchically porous Co/C foam with low density has been successfully prepared by a facile sequential process of foaming–lyophilization–carbonization. In the hierarchical structure, the macro- and mesoscopic pores are created by surfactant-assisted foaming and lyophilization processes, while the nanoscale pores spring from the etching reaction between gelatin-derived carbon and metal oxides during the high-temperature carbonization. By adjustment of the carbonization temperature and loading of the as-prepared absorbent, a maximum reflection loss (RL) achieves −56.5 dB at the thickness of 2.49 mm, and a broad effective absorption bandwidth (EAB) of 6.0 GHz is reached. The corresponding mechanism demonstrates that such an outstanding performance is rooted in the synergetic loss capacities from dielectric and magnetic components. Therefore, it is believed that this work provides a significant guidance for exploring high-performance and lightweight microwave absorbents.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
TALANTA
·
2024
·
IF 5.6
Xueli Yuan,Jing Kong,Ying Xie,Xinxin Liu,Wei Zhang,Tao Liu,Zhenyu Chu,Wanqin Jin
The abuse of kanamycin (KAN) poses an increasing threat to human health by contaminating agricultural and animal husbandry products, drinking water, and more. Therefore, the sensitive detection of trace KAN residues in real samples is crucial for monitoring agricultural pollution, ensuring food safety, and diagnosing diseases. However, traditional assay techniques for KAN rely on bulky instruments and complicated operations with unsatisfactory detection limits. Herein, we developed a novel label-free aptasensor to achieve ultrasensitive detection of KAN by constructing mesoporous DNA-cobalt@carbon nanofibers (DNA-Co@C-NFs) as the recognizer. Leveraging the extended π-conjugation structure, prominent surface area, and abundant pores, the Co@C-NFs can effectively load aptamer strands via π-π stacking interactions, serving as KAN capturer and reporter. Due to the change in DNA configuration upon binding KAN, this aptasensor presented an ultralow detection limit and ultra-wide linear range, along with favorable precision and selectivity. Using real tap water, milk, and human serum samples, the aptasensor accurately reported trace KAN levels. As a result, this convenient and rapid autosensing technique holds promise for onsite testing of other antibiotic residues in agriculture, food safety, and clinical diagnosis.
研究领域:
生物传感技术
·
食品安全检测
·
环境监测
·
医学诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Mengyi Zhang,Xiaohui Sun,Xudong Cai,Xiaolu Zhan,Yufei Wu,Xuyang Zhang,Guohua Wu,Xiangwei Wang
In the field of electromagnetic wave (EMW) absorption, carbon matrix materials based on metal–organic frameworks (MOFs) have drawn more interest as a result of their outstanding advantages, such as porous structure, lightweight, controlled morphology, etc. However, how to broaden the effective absorption bandwidth [EAB; reflection loss (RL) ≤ −10 dB] is still a challenge. In this paper, large microsphere structures of a Co/C composite composed of small particle clusters were successfully prepared by the solvothermal method and annealing treatment. At a filling ratio of 40 wt %, the Co/C composite shows attractive microwave absorption (MA) performance after being annealed at 600 °C in an atmosphere of argon. With an EAB of 6.32 GHz (9.92–16.24 GHz) and a thickness of just 2.57 mm, the minimum RL can be attained at −54.55 dB. Most importantly, the EAB can attain 7.12 GHz (10.88–18.0 GHz) when the thickness is 2.38 mm, which is larger than that of the majority of MOF-derived composites. The superior MA performance is strongly related to excellent impedance matching and a higher attenuation constant. This study provides a simple strategy for synthesizing a MOF-derived Co/C composite with a wide EAB.
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
Nanoscale
·
2023
·Vol. 15
·期 18
·8255-8269
·
IF 6.7
Huanhuan Wang,Qi Qu,Jiangshan Gao,Yan He
Herein, Fe3O4@MnO2@Ni–Co/C composites derived from PBAs were successfully fabricated. Firstly, Ni–Co Prussian blue analogues (Ni–Co PBAs) were used as precursors to derive a carbon layer on their surface by annealing treatment and subsequently translated into MnO2@Ni–Co/C nanocubes after hydrothermal reactions. Fe3O4@MnO2@Ni–Co/C composites were finally obtained after depositing Fe3O4 nanoparticles through the annealing process. Their electromagnetic wave (EMW) absorption performance apparently enhanced, thanks to the excellent impedance matching and strong attenuation derived from the synergy between the dielectric loss and the magnetic loss. In particular, the minimum reflection loss (RLmin) of Fe3O4@MnO2@Ni–Co/C reached −41.2 dB with a thickness of 4.0 mm and the effective absorption bandwidth (EAB) reached 7.1 GHz with a thickness of 2.0 mm. Therefore, the results could be significant for synthesizing EMW absorbers with excellent performance, a broad bandwidth, strong absorption, thin thickness and light weight.
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）