NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 33
·13962-13970
·
IF 3.288
Hengdong Ren,Jialin Ma,Jun Zhou,Xiangfeng Shu,Zhenying Liu,Yin Liu,Yan Zhao,Tao Ge,Fanfei Min,Ling Bing Kong
Anthracite-based carbon/Ni3Fe/NiO ternary composites were synthesized by using a microwave radiation method at a frequency of 915 MHz. Phase and elemental compositions of the composites were investigated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). According to FESEM observations, Ni3Fe and NiO particles are uniformly implanted into grid-like porous structures and interlayers on the surface of anthracite-based carbon. The carbonization was realized at 700 °C, which could be attributed to the presence of a large number of polar molecules in anthracite that responded actively to microwave irradiation. The oxygen-containing functional groups in anthracite-based carbon provide multiple relaxation processes. Therefore, the composites exhibited a minimum reflection loss of −51.66 dB at 5.52 GHz, with effective absorption covering the S and C bands. Importantly, this result shows a facile method for preparing coal-based carbon/magnetic powder, which utilizes the rapid reaction of microwave radiation.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 12
·1836
·
IF 5.3
Xiaomei Zhang,Baitong Zhou,Xiang Li,Runhua Chen,Chen Ma,Wenhua Chen,Guohua Chen
Microwave-absorbing materials have attracted extensive attention due to the development of electronic countermeasures. In this study, novel nanocomposites with core–shell structures based on the core of Fe-Co nanocrystals and the shell of furan methylamine (FMA)-modified anthracite coal (Coal-F) were designed and fabricated. The Diels-Alder (D-A) reaction of Coal-F with FMA creates a large amount of aromatic lamellar structure. After the high-temperature treatment, the modified anthracite with a high degree of graphitization showed an excellent dielectric loss, and the addition of Fe and Co effectively enhanced the magnetic loss of the obtained nanocomposites. In addition, the obtained micro-morphologies proved the core–shell structure, which plays a significant role in strengthening the interface polarization. As a result, the combined effect of the multiple loss mechanism promoted a remarkable improvement in the absorption of incident electromagnetic waves. The carbonization temperatures were specifically studied through a setting control experiment, and 1200 °C was proved to be the optimum parameter to obtain the best dielectric loss and magnetic loss of the sample. The detecting results show that the 10 wt.% CFC-1200/paraffin wax sample with a thickness of 5 mm achieves a minimum reflection loss of −41.6 dB at a frequency of 6.25 GHz, indicating an excellent microwave absorption performance.Keywords:anthracite coal;Diels-Alder reaction;microwave absorbing performance;core–shell structure
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 PROCESSING TECHNOLOGY
·
2021
·
IF 7.033
Rongyu Deng,Fulu Chu,Huanyu Yu,Felix Kwofie,Mingzhi Qian,You Zhou,Feixiang Wu
Expanded graphite has garnered considerable interest for potential applications in electrochemical energy storage due to its distinctive morphological and structural Li storage features. However, the present synthetic procedure of preparing expanded graphite is highly complex and yields low production. Herein, we demonstrate that an efficient microwave method can produce large-scale expanded graphite utilizing anthracite as a precursor. The designed expanded graphite exhibits a remarkably ordered graphitic structure and a unique morphology of porous layered gossamer nanosheets having a wider pore size distribution within the ranges of 3–70 nm and a practically huge specific surface area being 21.5 m 2 g −1 , which are beneficial for improving the conductivity of expanded graphite, inducing more active sites for electrochemical reactions and accelerating Li + diffusion. Furthermore, the expanded graphite demonstrates a promising capacity utilization of 278.0 mAh g −1 and a stable Coulombic efficiency of 99.17% during 300 cycles at 0.2C when it is employed as lithium-ion batteries anode material. Hence, this study presents a promising method for the large-scale production of expanded graphite materials as anodes for lithium-ion battery by exploiting natural anthracite as the low-cost raw material.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2022
·
IF 3.806
Xinmei Gao,Zhimeng Shen,Gaobo Chang,Zhong Li,Hanqing Zhao
Carbon materials have been widely used as the sodium ion batteries (SIBs) anodes. The pore structure and surface chemistry are critically important to improve the sodium storage performance. Here, the mechanochemistry assisted N-doping strategy was adopted to achieve pore regulation and pyridinic nitrogen doping in anthracite-derived carbon. The mechanochemistry method was conducive to introducing abundant mesopores, with the mesopore volume enhanced by 80 %–171 %. The mechanochemistry method facilitated the generation of abundant edge defects and sodium adsorption sites including pyridinic nitrogen and carbonyl groups. Therefore, the N-doped anthracite anode with improved Na + and electron dynamics, delivered an enhanced reversible capacity of 320.9 mA h g −1 under 0.03 A g −1 and retains 194.4 mA h g −1 under 1 A g −1 after 1000 cycles. This work offers a novel and green approach to adjusting pore structure and surface chemistry of coal-based carbon materials and promotes the large-scale application of SIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Yuzhen Zhang,Jun Dai,Juan Yang,Jianping Wei,Dongtao Wu,Chongchong Leng
The effects of alkali-activated potassium persulfate solution (AAP) immersion on coal surface wettability and pore structure were systematically investigated in this study. Experimental results indicated when mass fraction of potassium persulfate and sodium hydroxide was 1.5 % and 0.5 %, activation temperature was 30 °C, anthracite wettability was improved most significantly. Under the optimal conditions, capillary reverse osmosis height of the AAP-treated coal samples reached 8.1 cm, and water-droplet contact angle θ decreased markedly from 112.97° to 55.08°. Relative content of oxygen-containing groups –C O and OH–OH increased most significantly. Coal molecular structure models were constructed and theoretical simulation results showed that both H 2 O adsorption capacity and adsorption heat increased after AAP immersion, and the AAP-treated coal samples can absorb a large number of water molecules even at lower pressure. Spray dust-suppressing efficiency increased from 33.42 % to 74.65 % by using AAP. The radicals (SO 4 · − and · OH) in AAP could in-situ oxidize and corrode active organic molecules in coal matrix, expanding original pores and creating new pores-fractures on coal surface. Average pore diameter increased by 17.40 %, while specific surface area decreased by 51.14 %, and internal pore surface became smoother. Additionally, methane adsorption constant a and b value of the AAP-immersed coal samples decreased by 6.42 % and 32.68 %. Compared with previous reports on wettability regulation, this study not only enhanced the wettability of coal samples, but also improved their pore structure. These findings provide crucial technical support for innovative development of dust suppression and outburst prevention technologies in coal mines.
研究领域:
煤炭科学
·
表面化学
·
岩石学
·
环境工程
·
分子模拟
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 16
·5314
·
IF 4.927
Xuyang Bai,Guochao Yan,Xuanlai Chen,Jiajun Li
Ionic surfactants are widely used in coal dust control in mines, and their adsorption characteristics on the coal surface have a great influence on the coal dust control effect. In this investigation, anionic sodium dodecylbenzenesulfonate (SDBS) and cationic octadecyltrimethylammonium chloride (STAC) were selected to explore the adsorption characteristics of ionic surfactants on the surface of anthracite. The experimental results show that the adsorption rate and efficiency of STAC on the surface of anthracite are higher than that of SDBS; STAC can form a denser surfactant layer on the surface of anthracite, with a larger adsorption capacity and higher strength. Molecular dynamics simulations show that the adsorption between STAC and the surface of anthracite is tighter, and the distribution at the coal–water interface is more uniform; the surface of anthracite modified by STAC has a stronger binding ability to water molecules.Keywords:ionic surfactant;anthracite;adsorption characteristics
研究领域:
矿业工程
·
界面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 9
·1253
·
IF 4.034
Huihui Zeng,Baolin Xing,Lunjian Chen,Guiyun Yi,Guangxu Huang,Ruifu Yuan,Chuanxiang Zhang,Yijun Cao,Zhengfei Chen
A novel approach is developed to synthesize a nitrogen-doped porous Co3O4/anthracite-derived graphene (Co3O4/AG) nanocomposite through a combined self-assembly and heat treatment process using resource-rich anthracite as a carbonaceous precursor. The nanocomposite contains uniformly distributed Co3O4nanoparticles with a size smaller than 8 nm on the surface of porous graphene, and exhibits a specific surface area (120 m2·g−1), well-developed mesopores distributed at 3~10 nm, and a high level of nitrogen doping (5.4 at. %). These unique microstructure features of the nanocomposite can offer extra active sites and efficient pathways during the electrochemical reaction, which are conducive to improvement of the electrochemical performance for the anode material. The Co3O4/AG electrode possesses a high reversible capacity of 845 mAh·g−1and an excellent rate capacity of 587 mAh·g−1. Furthermore, a good cyclic stability of 510 mAh·g−1after 100 cycles at 500 mA·g−1is maintained. Therefore, this work could provide an economical and effective route for the large-scale application of a Co3O4/AG nanocomposite as an excellent anode material in lithium-ion batteries.Keywords:Co3O4nanoparticles;anthracite-derived graphene;nanocomposite;lithium-ion batteries
研究领域:
材料科学
·
电化学
·
纳米技术
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2016
·
IF 2.835
Zhen-Yi Du,Xia Wang,Yu-Hong Qin,Zhi-Hua Zhang,Jie Feng,Wen-Ying Li
The purpose of this study was to reveal the structural evolution of cellulose-derived tars in the biomass/coal co-gasification environment. A two-stage reactor was employed, where the pyrolytic vapors of cellulose were produced in the top stage and the secondary reactions of these vapors took place in the bottom stage under a range of conditions. The roles of anthracite char and steam were examined by implementing three operational modes in the bottom stage: thermal cracking (TC), catalytic cracking (CC), and catalytic reforming (CR), over a temperature range from 600 to 900 °C. Anthracite char was effective in enhancing tar reduction at lower temperatures (≤700 °C), above which its effect diminished. Tar yields under the CC and CR modes were comparable in the studied temperature range, suggesting the minimum effects of steam on the tar amount. However, gel permeation chromatography coupled with a diode array detector (GPC–DAD) and gas chromatography–mass spectrometry (GC–MS) characterization of tars showed that both anthracite char and steam had significant influence on the composition of tar, in terms of the molecular weight distribution and aromatic cluster sizes. Specifically, at a high temperature (900 °C), the presence of anthracite char facilitated the reduction of aromatic compounds, especially those with larger aromatic ring systems (≥3 fused benzene rings). In addition, the used anthracite chars showed lowered specific surface areas, which was postulated to be the main reason for their slightly reduced gasification reactivity.
研究领域:
能源工程
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2023
·
IF 5.3
Shanxin Xiong,Xueni Zhao,Fengyan Lv,Wei Zhang,Nana Yang,Yukun Zhang,Xiaoqin Wang,Ming Gong,Chenxu Wang,Zhen Li
Coal possessing high fixed carbon content can be used for the preparation of activated carbon materials, including supercapacitance electrode carbon. Taixi anthracite has less ash content and high graphitization degree, which is a good candidate as a carbon source, while its low chemical activity affects the pore growth during the activated process. In this paper, using Taixi anthracite as the raw material, the effects of H2O2 pre-oxidation on the pore structure, surface chemical structure, and electrochemical properties of prepared activated carbon were studied. The results show that H2O2 successfully reduces the hydrophobic characteristics of the coal surface, which provides the possibility for the accessibility of the activator and the electrolyte. The activated carbon with H2O2 treatment at 15% concentration (AC-15%) shows high specific surface area (2016.50 m2/g), high specific capacitance (262 F/g), and high rate performance (63%), which is much higher than AC-0% without the pre-oxidation treatment. It is due to that the stable oxygen-containing functional groups (aldehyde and anthraquinone) on coal can improve the activity of activation carbon material and increase the wettability without affecting the electrical conductivity. In addition, the material shows high energy density and cyclic stability. This study provides an effective surface treatment approach for the preparation of a high-performance coal-based supercapacitance electrode material.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION SCIENCE AND TECHNOLOGY
·
2016
·
IF 1.083
Zijian Su,Yuanbo Zhang,Jun Chen,Bingbing Liu,Guanghui Li,Tao Jiang
In this study, a process of magnetizing roasting followed by magnetic separation, which is used to separate or recover tin and iron from the high calcium type tin- and iron-bearing tailings (containing 35.53 wt.% Fe and 0.56 wt.% Sn), was investigated . A magnetic concentrate containing 66.3 wt.% Fe and 0.07 wt.% Sn with an iron recovery rate of 92.9 wt.% was obtained under optimal conditions: anthracite ratio of 2.5:100, roasting temperature of 850°C, roasting time of 30 min, grinding time of 10 min, and magnetic field intensity of 0.1 T. In addition, the effect of roasting parameters on the separation of iron and tin and phase transformation of SnO2 was investigated by using X-ray powder diffraction, Scanning Electron Microscopy–Energy Dispersive Spectroscopy, etc.
研究领域:
冶金学
·
矿物加工
·
材料科学
✓ 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）