Sustainable Energy & Fuels
·
2022
·Vol. 6
·期 10
·2602-2612
·
IF 6.813
Haosheng Xin,Haiyong Wang,Song Li,Xiaohong Hu,Chenguang Wang,Longlong Ma,Qiying Liu
Catalytic conversion of renewable cellulose, instead of fossil resources, to high-value ethylene glycol (EG) is of great significance for reducing considerable worries regarding the energy problem. However, the EG production from cellulose is dependent on Ni and Ru based catalysts. Herein, encapsulated Co@C catalyst was firstly applied for EG production from cellulose combined with tungstic acid (TA). The mixing of the two catalysts in different ratios was compared and well-controlled, and the highest 67.3% yield of EG can be achieved. TA is used mainly to promote both the cellulose hydrolysis and the retro-aldol reaction of glucose to glycolaldehyde. Co@C catalysts are responsible for the hydrogenation of glycolaldehyde to EG. Compared with traditional noble metals and composite catalysts, the inexpensive and easily synthesized Co@C catalysts could greatly reduce the cost of production of EG. The Co@C catalysts encapsulated with outside graphene layers can keep high stability for at least 6 runs.
研究领域:
化学工程
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催化
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可再生能源
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yun Tang,Jingqi Ruan,Yalou Xin,Xiaohu Ren,Hudie Yuan,Xianhu Liu,Qiang Chen
The development of metal–organic frameworks (MOFs)-derived magnetic carbon-based materials for high-efficiency electromagnetic wave (EMW) absorption has attracted widespread attention. While these MOFs-derived composites have shown exceptional performance in absorbing EMWs within the X and Ku bands, the pursuit of effective absorption at lower frequencies remains a challenge. Herein, we demonstrate a novel strategy to synthesize hollow Co@C/C rods with excellent C-band EMW absorption via acetic acid etching and pyrolysis of core–shell ZIF-8@ZIF-67. Based on acetic acid etching, ligand-deficient ZIF-8@ZIF-67 rods with abundant mesoporous structures are constructed, enabling precise control over the Co nanoparticles content, graphitization degree, and pyridinic N doping in the derived Co@C/C. This simple fine-tuning approach simultaneously reduces dipole polarization by lowering the pyridinic N doping concentration, suppresses interfacial polarization and conduction loss through reducing the number of graphitic carbon layer, and enhances magnetic loss by increasing the Co content. These combined effects collectively improve the impedance matching of Co@C/C for low-frequency absorption. Notably, as the volume of acetic acid solution increases, the absorption frequency band of Co@C/C gradually shifts from the Ku-band to the C-band, while sustaining superior EMW absorption performance. At the filling ratio of merely 11 %, the RL min values for Co@C/C-20 and Co@C/C-30 achieve −49.8 dB and −34.7 dB at 7.2 GHz and 6.8 GHz, respectively. This study offers a valuable approach to the development of lightweight materials with excellent EMW absorption in C-band.
研究领域:
材料科学
·
电磁学
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Gang Wen,Hui Liu,Tao Liang,Yunpeng Ouyang,Liang Tan,Renzong Hu,Jun Liu,Yao Zhang,Min Zhu
Despite there being many reports on SnO 2 -based anode materials, most of the electrode materials are tested in half cells using lithium metal with unlimited lithium-ion sources as the counter electrode, which may conceal the real properties of these composites to a certain extent. In this study, a ternary SnO 2 –Co–C composite was fabricated by a scalable ball milling strategy. The composite exhibited high initial Coulombic efficiency (ICE, >80%), a large capacity (∼900 mA h g −1 ) and superior cycling stability (capacity retention more than 99% after 100 cycles) in half cells. Furthermore, coin-type full cells in which the ternary SnO 2 –Co–C anodes were paired with different cathodes were demonstrated. A LiFePO 4 ||SnO 2 –Co–C full cell tested at 0.5–3.4 V exhibited an ICE of 75.1% and an initial discharge capacity of 906 mA h g −1 , which were close to those of the SnO 2 –Co–C||Li half cells. By analyzing the cycling performance and characteristics of the charge/discharge process for the full cells with different capacity ratios of cathode/anode, it was confirmed that the capacity decay of the full cells was due to the continuous consumption of Li + ions during cycling. Hence, the testing voltage windows were adjusted according to the lithiation/de-lithiation behavior of the SnO 2 . On this basis, the LiFePO 4 ||SnO 2 –Co–C full cells tested at 2.3–3.4 V and the LiCoO 2 ||SnO 2 –Co–C full cells tested at 2.60–3.75 V exhibited excellent cycling stability, demonstrating 80.3% and almost 100% capacity retention after 100 cycles, respectively, thereby laying a foundation for the practical application of advanced SnO 2 -based anodes in lithium-ion batteries.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 16
·7206-7220
·
IF 9.931
Tao Liang,Renzong Hu,Houpo Zhang,Hanyin Zhang,Hui Wang,Yunpeng Ouyang,Jun Liu,Lichun Yang,Min Zhu
A new ternary SnO2–Co–C composite is produced using a facile and scalable ball milling method, which has a microstructure that includes refined SnO2–Co hybrids embedded in graphite. The Co additives dramatically inhibit Sn coarsening in the lithiated SnO2, which enables highly reversible conversion reactions in the SnO2-based ternary composite during cycling. The electrodes exhibit high ICEs with an average of 80.8% and a reversible capacity of 780 mA h g−1 at 0.2 A g−1 after 400 cycles when the composite was manufactured via small planetary ball milling, and they achieve 875 mA h g−1 after 250 cycles when the material is prepared on a large-scale with a roller mill. Even at a high rate of 2 A g−1, the composite has a long lifetime and delivers 610 mA h g−1 after 1000 cycles. Furthermore, a stable capacity of 410 mA h g−1 can be also retained in a full cell combined with a LiFePO4 cathode and SnO2–Co–C anode when cycling within 2.3–3.4 V at 0.2C. The new ternary SnO2–Co–C composite demonstrates excellent comprehensive electrochemical performances, and it is a promising candidate anode material for use in practical applications.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
·
IF 9.136
Li Huang,Xiangyu Chen,Bing Wan,Shuxia Xu
Norfloxacin (NOR) is a highly toxic fluoroquinolone antibiotic, which is continuously discharged into aquatic environment. Due to its poor biodegradability, NOR is difficult to be removed and has exerted a serious impact on environmental risk. In this paper, a coaxial double dielectric barrier discharge (DBD) device was designed and built, then was synergic with cobalt-carbon (Co@C) composites for the improved degradation of NOR in wastewater with high degradation efficiency. The Co@C composite, a porous carbon material, was synthesized by calcination of Co-metal organic frameworks (Co-MOFs), and was further characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Brunauer-Emmett-Teller surface analyzer, Fourier transform infrared spectrometry and vibrating sample magnetometer. The combination of DBD with Co@C system has an obvious synergistic effect for the removal of NOR. The degradation rate could reach to 84.7% and the treatment time was in 15 min, which were 14.1% higher and 10 min shorter than those of solo DBD system. The synergistic factor was estimated to be 1.12, and the energy yield of process could reach to the maximum of 7.6 mg/kWh. The effects of discharge voltage, pH, NOR initial concentration and Co@C dosage on the degradation rate of NOR have been explored in detail. The experimental results indicated that the system of DBD coupled with Co@C for NOR degradation was appropriate in a wide initial pH from 3.0 to 11.0. Moreover, Co@C could be reused several times and convenient to be magnetically recycled. Furthermore, it was proved that O 3 , • OH and H 2 O 2 were the main reactive oxygen species during the catalytic decomposition reactions of NOR, and the generated O 3 in DBD system could be converted into • OH under the synergic catalysis of Co@C, further promoting degradation efficiencies for NOR. Finally, main intermediate products of NOR degradation were analyzed by liquid chromatography-mass spectrometry, and possible degradation mechanism and pathways were speculated.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2020
·
IF 12.35
Shangbo Ning,Hua Xu,Yuhang Qi,Lizhu Song,Qiqi Zhang,Shuxin Ouyang,Jinhua Ye
The transformation of CO2 into a single product is a critical scientific challenge because of the difficulty associated with targeted activation and conversion of CO2 by heterogeneous catalysts. Herein, we present an atomic-scale dispersed Co–N species anchored Co@C hybrid structure (entitled as Co@CoN&C) that regulates catalytic properties in thermodynamic and kinetic processes to achieve active and highly selective CO yield in the photothermal CO2 reduction. An optimal sample delivers the maximum yield rate of 132 mmol gcat.–1 h–1 and remarkable CO selectivity (91.1%), while the undesirable methanation activity, compared with typical Co nanoparticles (NPs), was suppressed. The mechanism study suggests that the strong photon–matter interaction over graphitic-carbon and Co NPs can enhance the light-to-heat conversion efficiency and thus induce the high work temperature, which is thermodynamically beneficial for CO2 activation and subsequently promoted the catalytic activity. Furthermore, the carbon layers improve the adsorption of CO2, and the surface atomically dispersed Co–N species weakens hydrogenation capability, which kinetically controls the reaction pathway and therefore attains the high selectivity for CO production. This study exemplifies that the microstructure design can modulate the thermodynamic and kinetic factors of photochemical reaction and thereby achieve potential solar-to-chemical energy conversion.
研究领域:
材料科学
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催化化学
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能源转换
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2020
·Vol. 22
·期 27
·4591-4601
·
IF 3.117
XiuBo Xie,Cui Ni,Hongying Yu,Wei Du,Xueqin Sun,Dongbai Sun
Core@shell-structured Co@C nanoparticles (NPs) were designed in this work. The shell thickness of carbon at 2.0, 3.2, 3.6, 4.0, and 4.7 nm was tuned by changing the weight ratio (Co : glucose = 2 : 1, 1 : 1, 1 : 2, 1 : 4, 1 : 10) of glucose in the reaction process. The influences of the carbon-shell thickness on the electromagnetic parameters and catalytic activity of the nanocrystalline Co were studied. Among the five samples, the Co@C-21 NPs (carbon-shell thickness of 2.0 nm) mixed with paraffin wax (PW) showed the best reflection loss (RL) of −42.5 dB at 16.1 GHz, while the Co@C-11-PW composite (carbon shell thickness of 3.2 nm) exhibited the best absorption bandwidth for RL < −10 dB of 9.6 GHz (8.4–18.0 GHz) with a matching thickness of 2.6 mm. The natural/exchange resonances, interfacial polarization, and uniformly dispersed Co NPs led to a high microwave absorption performance of the Co@C absorber with good impedance matching. Moreover, as a catalyst for the model removal reaction of 4-nitrophenol (4-NP), the Co@C-110 NPs with a shell thickness of 4.7 nm showed the best kinetic rate constant of 0.31 min−1, 4.3 times higher than that of the Co@C-21 NPs. The Co@C NPs are a potential microwave absorber and effective catalyst for the reduction of 4-NP.
研究领域:
材料科学
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Linyun Zhang,Shanxin Li,Xuzhou Jiang,Hongying Yu,Yijing Sun
Metal organic frameworks (MOFs) have been widely used as microwave absorption (MA) materials owing to their varied structures and large specific surface area. However, it is still challenging to endow MOF derivatives with a rational structure to achieve outstanding microwave absorption. In this work, the hollow Co@C nanorods (HCCN) with lots of winding carbon nanotubes on the surface are obtained based on a template-sacrificing method which employs ZnO nanorods as templates and ZIF67 nanoparticles as ornaments. The HCCNs possess large pore size and specific surface area, efficiently improving the impedance matching . The 1D structure, abundant heterointerfaces and defects trigger strong conduction loss, interfacial and dipole polarization, respectively. Therefore, HCCNs exhibits excellent MA properties: the strong reflection loss of −66.8 dB at the thickness of 2.1 mm and the effective absorption bandwidth of 5.68 GHz at 2.5 mm. Radar cross section (RCS) simulation results have confirmed the practicality of HCCNs. This study proposes an inspiration for the structural designing of MOF materials and derivatives to realize amazing MA performance.
研究领域:
材料科学
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纳米技术
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电磁材料
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Peidong Hong,Zijian Wu,Dandan Yang,Kaisheng Zhang,Junyong He,Yulian Li,Chao Xie,Wu Yang,Ya Yang,Lingtao Kong,Jinhuai Liu
Singlet oxygen ( 1 O 2 ) is an electrophilic species that has great selectivity for breaking down electron-rich refractory organic pollutants. However, in most cases, 1 O 2 plays a minor role in the Fenton-like process due to its low yield, the contributions of which are usually covered by free radicals. Here, we provide the first report on a type of hollow amorphous Co/C composites prepared for the efficient generation of 1 O 2 to degrade oxytetracycline (OTC) selectively in the Fenton-like system. The optimized Co/C samples (Co/C-3) obtained the best degradation performance of OTC near to 100% under neutral conditions, along with satisfactory reusability and stability. Additionally, it exhibited a high anti-interference capacity for inorganic anions and natural organic matter s in the different water qualities. XPS spectrum revealed that the electron cycle of ≡Co 2+ -O-C/H and ≡Co 3+ -O-C/H played a vital effect on the formation of 1 O 2 . Quenching experiments and EPR testing further verified that 1 O 2 converted from ·O 2 – was the dominant oxidative species, and no hydroxyl radical (·OH) appeared in this reaction. Moreover, the results of the Fukui function and T.E.S.T (Toxicity Estimation Software Tool) analysis provided significant assistance in the exploration of degradation pathways and ecological risks of OTC and its intermediates.
研究领域:
环境科学
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材料科学
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污染控制
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Ying Liu,Xiaoyan Chen,Yulin Yang,Yong Feng,Deli Wu,Shun Mao
Cobalt-based nanostructures have shown a great potential for radical production by activating persulfate (PS). Here, we report a facile strategy to synthesize nitrogen-doped porous Co@C nanoboxes (Co@NC) by pyrolysis of zeolitic imidazolate frameworks (ZIF-67), followed by partially etching away the metallic cobalt. With a nitrogen-enriched hollow porous carbon nanobox and embedded Co nanoparticles, the Co@NC shows high efficiency in PS activation for p-Chloroaniline (PCA) removal. The degradation study shows that a complete removal of high concentration PCA is done within two minutes, which is superior to most of the reported PCA removals with PS-based advanced oxidation processes (AOPs). More importantly, the Co@NC exhibits high catalytic activities in a wide range of pH from 5 to 9. The Co@NC also shows very limited Co 2+ release with a dissolution proportion of 0.28%, much lower than previously reported Co-based catalysts, and remains high efficiency after five successive reaction cycles. A heterogeneous activation mechanism though surface reaction is proposed, in which PCA firstly absorbs on the carbon nanobox surface, then being oxidized by generated radicals and non-radical species. The unique structure and outstanding performance of Co@NC catalysts present new insights in catalyst design for PS-based advanced oxidation for organic pollutants removal in waste water.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Reaction Chemistry & Engineering
·
2022
·Vol. 8
·期 1
·64-76
·
IF 5.2
Haosheng Xin,Haiyong Wang,Xiaohong Hu,Xiuzheng Zhuang,Long Yan,Chenguang Wang,Longlong Ma,Qiying Liu
Cellulose hydrolysis and further conversion to diketones and alcohols was performed with graphene layer encapsulated cobalt catalysts (Co@C) in phosphoric acid aqueous solution. A total of 60.5% yield of the products mainly including ethanol, 2,5-hexanedione (2,5-HD) and diols could be achieved in 0.06 M H3PO4 solution. A series of characterization methods such as XRD, XPS, TEM, TG-MS, BET, ICP, H2-TPD, NH3-TPD, and Raman were carried out to explore the catalyst formation mechanism and reaction activity. The results of the analysis indicated that the calcination temperature had a deep influence on the structure formation of the Co@C catalysts, thus leading to differences in the reaction activity. While the calcination temperature was determined at 700 °C, the Co@C catalyst meets with the requirements of optimal reaction activity, appropriate particle size, suitable surface area, and pore size. Besides, it was found that H3PO4 is not only favorable in cellulose hydrolysis but also cooperates with the Co@C catalyst in the hydrogenolysis of C–O bond and C–C bonds for the formation of products. This work provides a possible way for renewable cellulose conversion to diketone and alcohols over encapsulated non-noble metal catalyst combined with phosphoric acid aqueous solution.
研究领域:
化学工程
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催化
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Yang Wang,Lei Zhang
In order to eliminate multiple coexisting pollutants in environmental wastewater, a magnetic three-dimensional hierarchical porous flower-like N, Co-doped graphitic carbon nano-polyhedra decorated NiCo-layered double oxides (N-Co@C/NiCo-LDOs) adsorption material was synthesized, which consisted of two-dimensional LDOs nanosheets with functionalized surfaces (N, Co-doped graphitic carbon loaded on both sides of NiCo-LDOs nanosheets). The adsorption properties of N-Co@C/NiCo-LDOs for five types of typical pollutants (cationic dyes: rhodamine b, methylene blue ; pesticides: ethofenprox, bifenthrin ; anionic dyes: methyl orange, congo red; inorganic cations : Cr 2+ , Cd 2+ , Pb 2+ , Zn 2+ , inorganic anions : Cr 2 O 7 2− , AsO 3 3− ) were investigated systematically in single and coexisting systems. Combined with the results of FTIR and zeta potential , the adsorption mechanism was discussed. By virtue of its hierarchical porous architecture and the combined effect of functionalized surfaces and LODs supporter, the as-prepared N-Co@C/NiCo-LDOs demonstrates excellent adsorption performance towards five types of typical pollutants with fast adsorption rate, high adsorption capacity and good co-adsorption performance. More importantly, the N-Co@C/NiCo-LDOs showed satisfactory removal efficiency, stability and reusability in model wastewater. The broad-spectrum, rapid, easily separable, and reusable adsorption properties make N-Co@C/NiCo-LDOs promising for highly efficient wastewater treatments . This work also provides a feasible way for the preparation of adsorption materials for the treatment of complex wastewater systems.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）