CHEMOSPHERE
·
2022
·
IF 8.943
Dongdong Liu,Dengqian Chen,Zhengkai Hao,Yibo Tang,Lipeng Jiang,Tianqi Li,Bing Tian,Cuiping Yan,Yuan Luo,Boyin Jia
In this work, a comparative study of efficient degradation of Rhodamine B (RhB) in CoFe 2 O 4 /H 2 O 2 and CoFe 2 O 4 /PMS systems was performed. Batch experiments indicated that the RhB degradation rate of CoFe 2 O 4 /H 2 O 2 system reached 95.5% at 90 min under the condition of 0.5 g L −1 of CoFe 2 O 4 dosage, 10 mM of H 2 O 2 concentration and 3.0 of initial pH. At certain conditions of initial pH = 7.0, 0.3 g L −1 of CoFe 2 O 4 dosage, 7 mM of PMS concentration, CoFe 2 O 4 /PMS system could completely degrade RhB within 90 min. EPR and quenching experiments indicated that •OH was the main active species of CoFe 2 O 4 /H 2 O 2 system, and •OH, SO 4 • - , •O 2 − and 1 O 2 participated in RhB degradation of CoFe 2 O 4 /PMS system. The circulate of Co(II)/Co(III) and Fe(II)/Fe(III) on the CoFe 2 O 4 surface promoted the formation of free radical species in the two system. In CoFe 2 O 4 /PMS system, the formed •O 2 − and SO 5 • - realized the generation of non-free radical species ( 1 O 2 ). The LC-MS results indicated that N -de-ethylation, chromophore cleavage, opening rings and mineralization were the main steps for the RhB degradation of the two systems. After five cycles of degradation experiment, the CoFe 2 O 4 /H 2 O 2 and CoFe 2 O 4 /PMS systems still maintained the high degradation rate (85.2% and 92.4%) and low mass loss (2.7% and 3.09%). In addition, CoFe 2 O 4 /PMS system had better potential value for the actual water and multi-pollutant degradation than CoFe 2 O 4 /H 2 O 2 system. Finally, the toxicity analysis and cost assessment of the two oxidation systems were preliminarily evaluated.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 16
·13469-13476
·
IF 2.22
Wang Li,Yang Chaoqun,Jin Hongjun,Hu Yue,Li Ji,Xu Shichong,Li Haibo
CoFe 2 O 4 /CoFe 2 nanocomposites with exchange coupling behavior have been obtained from a two-step process. First, CoFe 2 O 4 nanoparticles with size of 11 nm were synthesized using a co-precipitation method. And second, the as-synthesized CoFe 2 O 4 nanoparticles were reduced under mixed gas (Ar 95% + H 2 5%) for 1 h at different temperatures. The structure, phase, particle size, morphology, and magnetic properties with the reduction temperature were studied. X-ray diffraction and Mössbauer spectroscopy results show the whole process from pure CoFe 2 O 4 hard magnetic phase to pure CoFe 2 soft magnetic phase when the reduction temperature increases from 400 to 700 °C, and CoFe 2 O 4 /CoFe 2 hard/soft nanocomposites are obtained at 500 and 600 °C. Magnetic measurement result show there is a stronger exchange coupling interaction between CoFe 2 O 4 and CoFe 2 for the sample reduced at 500 °C, but not in the sample reduced at 600 °C. A giant 76% enhancement of the maximum magnetic energy product (BH) max compared with pure CoFe 2 O 4 will be of technological significance in the future.
研究领域:
材料科学
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磁学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Ying Liu,Rentao Xu,Xiaolong Gong,Cheng Yao,Shunlong Pan
The increased discharge of organoarsenic to natural waters, brings significant risks to ecosystems and human health. It is curial to rapidly transform organoarsenic to harmless arsenate (As(V)) before conventional coagulation-sedimentation treatment. In this study, the roxarsone (ROX) was destroyed to form As(V) with almost 100 % transformation rate and reaction rate of 0.43 min −1 via the CoFe 2 O 4 /peracetic acid (PAA) system. Specifically, PAA was primarily activated to form singlet oxygen ( 1 O 2 ) and organic radicals (R-O·) by Co(II)/Co(III) redox cycle existed on the CoFe 2 O 4 surface, the presence of iron (Fe) in the CoFe 2 O 4 facilitated the transformation of Co(III) to Co(II), and then that reactive oxygen species (ROS) was employed to mineralize ROX. The presence of common anions, and natural organic matters (NOM) hardly inhibit the degradation of ROX. Furthermore, the catalytic efficiency of CoFe 2 O 4 /PAA system remained above 94 % after five cycles. These findings suggest that the CoFe 2 O 4 /PAA system is a promising technique for enhanced arsenic decontamination.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Jun He,Sheng Liu,Lianwen Deng,Dongyong Shan,Can Cao,Heng Luo,Shuoqing Yan
Ti 3 C 2 MXene has demonstrated to be a potential microwave absorber if some difficulties, e.g., poor impedance matching and lack of magnetic loss, can be well-solved. In this paper, laminated Ti 3 C 2 MXene was synthesized using the HF etching method. CoFe 2 O 4 nanoparticles-decorated Ti 3 C 2 MXene (CoFe 2 O 4 -Ti 3 C 2 ) composites were then fabricated via a novel in-situ solvothermal process. The incorporation of CoFe 2 O 4 nanoparticles on the electromagnetic (EM) and microwave absorption properties of Ti 3 C 2 MXene were systematically studied over 2–18 GHz. Interestingly, increased percolation threshold and controlled complex permittivity were well-observed in the CoFe 2 O 4 -Ti 3 C 2 composites. Furthermore, additional magnetic loss due to the existence of magnetic CoFe 2 O 4 was easily obtained. Benefiting from tunable electromagnetic properties, the minimum reflection loss (RL) value of the CoFe 2 O 4 -Ti 3 C 2 -filled absorbing coating achieved −30.9 dB with a matching thickness of only 1.5 mm. A wide effective absorption bandwidth (RL < −10 dB) of 8.5 GHz was correspondingly realized. These results demonstrated that the CoFe 2 O 4 -Ti 3 C 2 composites are favorable as a broadband microwave absorbent.
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
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Xiaoli Li,Haijun Lu,Yun Zhang,Fu He
In this study, the polypyrrole/CNTs-CoFe 2 O 4 magnetic nanohybrid (CNTs-CoFe 2 O 4 @PPy) was prepared and then used as adsorbent and catalyst to remove anionic and cationic dyes. The hybrid material was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), elemental analysis, BET surface area, Fourier transform infrared (FTIR) spectroscopy and vibrating sample magnetometer (VSM). Adsorption behaviors of the as-prepared composites for anionic dyes such as Methyl Blue (MB), Methyl Orange (MO) and Acid Fuchsin (AF) were conducted where the effects of solution pH, initial dye concentration, contact time and ionic strength were systematically studied. The equilibrium adsorption data of MB, MO and AF were well fitted to the Langmuir isotherm model, yielding the maximum monolayer adsorption capacity of 137.00, 116.06 and 132.15 mg/g, respectively. Adsorption kinetics was best described by the pseudo-second order model. The introduction of CoFe 2 O 4 into CNTs-CoFe 2 O 4 @PPy hybrid could not only provide an effective magnetic separation performance, but also act as catalyst to activate peroxymonosulfate (PMS) for the degradation of cationic dye, Methylene Blue (MEB), from aqueous solution. The results showed that CNTs-CoFe 2 O 4 @PPy presented higher catalytic activity, better stability and reusability for the decolorization of MEB, resulting in an almost complete removal of 50 mg/L MEB after 30 min with 1.0 g/L catalyst and 4 mmol/L PMS . The characteristics of high adsorption capacity, effective separation, excellent catalytic activity and good reusability would make CNTs-CoFe 2 O 4 @PPy a promising candidate for wastewater treatment.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2023
·
IF 3.9
Hongyu Liu,Xin Wen,Jun Zhang,Huan Zhang,Junfu Wei
Catalytic oxidation of contaminants by peroxomonosulfate (PMS) was coupled with membrane filtration to realize high-performance removal of dyes. CoFe 2 O 4 (CFO) was enwrapped and cross linked in calcium alginate (CaAlg) to form CFO−CaAlg composite membrane. The introduction of CFO could not only activate PMS, but also enhanced the stability, hydrophilic property and crosslinking degree of the composite membrane. The final removal rate was enhanced greatly benefiting from the synergistic effect of filtration and catalytic degradation. The removal rate increased from 75% (filtration) to 98% by coupling with catalytic degradation. More importantly, purified water could be obtained immediately instead of waiting for purifying the whole feed solution due to the superiority of cross flow filtration . Radicals quenching and electron spin resonance (ESR) analysis experiment confirm that SO 4 · − contributed 25% and 1 O 2 contributed 75% in catalytic degradation. The composite membrane was effective for different type of dyes and could be reused only being backwashed by purified water because the catalyst CoFe 2 O 4 could recover from Co 3+ to Co 2+ by itself during the process. This study opens a new path of rapid water purification and immediate drinking water supply.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Jin-Tao Du,Hao Wu,Yao Jie,Yi Xia,Zhenyu Yang,Hong Yan,Qian Wang,Jie-Xin Wang,Jian-Feng Chen
Efficient and sustainable recycling of polyethylene terephthalate (PET) is essential in mitigating its environmental impacts on climate, human health, and global ecosystems. Glycolysis, a closed-loop recycling method that converts PET into bis(2-hydroxyethyl) terephthalate (BHET), stands out as one of the most promising methods due to its mild operating conditions and environmentally friendly nature. However, the complete convert PET into BHET with a high stability are still challenging. In this study, magnetically recyclable CoFe 2 O 4 nanocatalysts were synthesized by the solvothermal method and surface-modulated with Na 3 Cit·2H 2 O as a modifier. When utilizing an optimized CoFe 2 O 4 catalyst, conversion of PET achieved 100 %, with a BHET yield of 91.7 % at 210 °C for 1 h. The excellent catalytic performance of CoFe 2 O 4 is attributed to its smaller particle size, improved dispersion, higher surface Co/Fe ratio, and increased oxygen vacancies, all of which can be achieved through straightforward surface modulation. DFT calculations of M−O distance (M = Co or Fe), adsorption energy, and Bader charges confirm that a higher surface Co/Fe ratio enhanced PET glycolysis, consistent with experimental results. Additionally, a modified energy economy coefficient ( ε m ) was proposed to characterize the catalytic efficiency. The ε m value of CoFe 2 O 4 -60 % was 0.624, indicating promising applications in efficient PET glycolysis. This work presents a versatile approach for easily manipulating the surface properties of magnetic catalysts and identifies key factors for achieving high performance in PET-to-BHET conversion. It offers valuable guidelines for the future design of nanoparticle catalysts with magnetic properties for chemocatalytic reactions.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2020
·
IF 7.183
Ying Wang,Yuqing Zhang,Jiaqi Wang
To enhance the cleaning efficiency of the ultrafiltration membrane for wastewater, nano spinel CoFe 2 O 4 was synthesized on diatomite via hydrothermal reaction strategy to prepare nano spinel CoFe 2 O 4 deposited diatomite (CF/Dt) particles for activating peroxymonosulfate (PMS), and then used as a functional layer to form CF/Dtcatalytic separation membrane (CF/Dt-M) to remove small and medium molecular pollutants by precise separation and catalytical oxidation . CF/Dt particles and CF/Dt-M were characterized by SEM. The CF/Dt-M was used to deeply clean simulated wastewater containing oil and rhodamine B for investigating its separation and catalytic oxidation performances. The results show that nano spinel CoFe 2 O 4 particles with diameter of 20–100 nm are deposited on the surface of diatomite, and the thickness of CF/Dt-M functional layer is 44 μm. After cleaning simulated wastewater using CF/Dt-M, concentration of oil, RhB and COD in permeate reduces from 57 mg L −1 , 20 mg L −1 , 231 mg·L −1 to 8 mg·L −1 , 0 mg L −1 and 47 mg L −1 , respectively. Water yield of CF/Dt-M is 658 L m −2 h −1 under 0.06 MPa. Nano spinel CoFe 2 O 4 in CF/Dt-M can efficiently activate a small amount of PMS to release a lot of SO 4 •- , making CF/Dt-M perform properties of precise separation and catalytic oxidation. Therefore, CF/Dt-M is a promising candidate extensively applied for cleaning wastewater.
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
PROPELLANTS EXPLOSIVES PYROTECHNICS
·
2019
·Vol. 45
·期 3
·463-471
·
IF 1.634
Ming Zhang,Fengqi Zhao,Yanjing Yang,Ting An,Wengang Qu,Hui Li,Jiankan Zhang,Na Li
Three kinds of ferrates (NiFe 2 O 4 , ZnFe 2 O 4 and CoFe 2 O 4 ) were prepared via the facile solvothermal method and characterized using SEM, TEM, XRD, XPS, FT-IR and BET instruments. The NiFe 2 O 4 , CoFe 2 O 4 and ZnFe 2 O 4 particles possess hollow structure with average particle size of 70, 220 and 360 nm, respectively. The catalytic performance of the ferrates for AP thermal decomposition were studied using DSC and TG-DTG methods, and the decomposition mechanism of AP were suggested. The catalytic effects of different ferrates for AP thermal decomposition were significantly different. The CoFe 2 O 4 has the best catalytic activity, and the high thermal decomposition peak temperature ( T HDP ) and apparent activation energy ( E a ) of AP were decreased by 108.99 °C and 37.38 kJ mol −1 in the presence of CoFe 2 O 4 sample. Adding ferrates has no obvious influence on the gas-phase decomposition products of AP, but has a great influence on the energy barrier of high temperature decomposition of AP. The excellent catalytic activity of CoFe 2 O 4 is mainly attributed to the synergistic interaction between Fe and Co, which is conducive to the thermal decomposition of AP.
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
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Heqing Fu,Yin Wang,Weifeng Chen,Wei Zhou,Jing Xiao
A novel silanized CoFe 2 O 4 /fluorinated waterborne polyurethane (SC/FWPU) pressure sensitive adhesive was synthesized and characterized by atomic force microscopy (AFM), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and contact angle tester. The adhesive properties were measured in a test machine. Experimental results showed that the hydrophobicity, thermal stability, dynamic mechanical properties, as well as adhesive properties of SC/FWPU were improved with the incorporation of SC into FWPU. The dynamic hydrophobicity can be well described by the wetting kinetic model. The spreading-penetration parameter increased with an increase in SC content. The higher the spreading-penetration parameter is, the faster the contact angle reaches equilibrium, and the faster the SC/FWPU pressure sensitive adhesive penetrates and spreads.
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
CHEMOSPHERE
·
2019
·
IF 5.108
Liying Wu,Qian Zhang,Junming Hong,Zhengyu Dong,Ji Wang
This research describes the function of oxygen vacancy on CoFe 2 O 4-x for persulfate (PS) activation. Novel CoFe 2 O 4-x with different vacancy degrees that were successfully developed via hydrogen calcination were characterized using X-ray diffraction analyzer (XRD), Fourier transform infrared (FTIR) spectra, Raman spectroscopy , scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), H 2 temperature-programmed reduction (H 2 -TPR), cyclic voltammetry (CV), electrochemical impedance spectra (EIS), nitrogen adsorption-desorption isotherms and dynamic light scattering. The activation of catalysts was analyzed using Bisphenol A (BPA) as pollutant, and the main active species generated during the reaction were identified by using N 2 bubbling and scavenger experiments. Possible oxidation degradation pathways of BPA were speculated using gas chromatography–mass spectrophotometry (GC-MS) and total organic carbon (TOC) analysis. Findings indicated that the oxygen vacancies promoted electronic transfer and participated in the redox cycle from Co 3+ /Fe 3+ to Co 2+ /Fe 2+ to generate 1 O 2 and O 2 - . O 2 - , OH and SO 4 - generated from oxygen vacancy; moreover, PS activation could further degrade BPA to small molecules, such as benzenes and quinones . Finally, the toxicity of the reaction mixtures was evaluated and found that the acute toxicity to Daphnia magna decreased after 120 min treatment.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Yuruo Zheng,Ghulam Hussain,Changcheng Zheng,Xiaoqi Zhou,Man Zhang,Suirong Xie,Qianhe Yin,Shuyi Li,Batool Shanta,Xiawa Wang
Structure engineering is a powerful tool for tuning various properties and making CoFe2O4 (CFO) a prime candidate for electrocatalyst applications, especially in improving the oxygen evolution reaction (OER) performance. In this work, we explored rhenium substituents to replace cobalt and iron atoms of the CFO and obtained significant differences with the same doping level. The sol–gel process was employed to prepare the nanoparticles of Co1−zRezFe2O4 and CoFe2−zRezO4 (z = 0, 0.05). A detailed structural evaluation using Mössbauer spectroscopy verified the pure phase cubic spinel-type structure with a noticeable change in morphology by substituting Re. The OER and electrochemical impedance spectroscopy (EIS) were performed and showed better performance in the Fe-site doped structure. To explain the differences in the OER performance of the samples, X-ray photoelectron spectroscopy (XPS) on all elements, low-temperature Raman, and the density of states simulated by density-functional theory (DFT) were performed. We found that Re actively changed the properties of the structures and the doping on Fe-site enabled more oxygen vacancy and a higher ratio of cations in octahedral sites, which led to enhanced catalytic performance. This work provides a deep insight into the mechanism that influences the OER properties with Re doped in different sites, indicating a promising application of CFO as a catalyst material.
研究领域:
材料科学
·
电化学
✓ 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）