APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Xin Wang,Baofang Jin,Ruixue Feng,Wei Liu,Duan Weng,Xiaodong Wu,Shuang Liu
In this work, tandem oxygen delivery systems were built by coating cube-like Co 3 O 4 with Ag/CeO 2 , which exhibited high soot oxidation activity that overwhelmed the Fe 2 O 3 -based catalysts. The results of TPR and activity tests indicated that a large amount of Co 3 O 4 lattice oxygen could be transferred into O x − with the assistance of Ag/CeO 2 . These active oxygen species accelerated the oxidation of soot and NO at low temperature. Furthermore, the Co 3 O 4 -CeO 2 synergy facilitated Co 3+ → Co 2+ transformation during reactions, resulting in boosted NO conversion and thereby NO 2 -assisted soot combustion at mild and high temperatures. Given the Ag/Co 3 O 4 @CeO 2 -type catalysts were low-cost, hydrothermally stable and could be fabricated via co-precipitation methods easily, they were highly promising for application in both gasoline and diesel particulate filters.
研究领域:
催化
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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
Catalysis Science & Technology
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2016
·Vol. 6
·期 19
·7273-7279
·
IF 5.287
Guozhu Chen,Qihui Xu,Yong Wang,Guolong Song,Cuncheng Li,Wei Zhao,Weiliu Fan
It is still an important issue to develop a facile, environmentally friendly way to synthesize bimetal oxide materials. In this paper, Co3O4–CeO2 core–shell catalysts were prepared by an interfacial reaction, where Co(CO3)0.35Cl0.2(OH)1.1 nanorods were dispersed in Ce3+ aqueous solution for 2 days, followed by a calcination step. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Based on the characterization and comparative experimental results, we proposed that the OH− ions slowly dissociated from the Co(CO3)0.35Cl0.2(OH)1.1 precursor combined with Ce3+ to develop into Ce(OH)3 nanoparticles because of its smaller solubility product constant than that of the Co precursor or Co(OH)2. Neither an additional precipitation agent nor stabilizing molecules were employed during the whole preparation. Raman spectroscopy and H2-temperature programmed reduction (H2-TPR) analysis revealed that there is a synergistic effect between Co3O4 and CeO2 in the as-prepared Co3O4–CeO2 core–shell catalysts, which is responsible for their enhanced catalytic activity toward CO oxidation in comparison to pure Co3O4 and CeO2.
研究领域:
催化材料
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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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2012
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IF 5.625
Ting Bao,Zhongkui Zhao,Yitao Dai,Xiaoli Lin,Ronghua Jin,Guiru Wang,Turghun Muhammad
CO preferential oxidation (PROX) reactions were performed over the supported Co 3 O 4 -CeO 2 catalysts on modified activated carbon (AC) for eliminating the trace CO from H 2 -rich gases. The effects of support modification by H 2 O 2 oxidation treatment , catalyst calcination temperature, Ce/Co atomic ratio ( n Ce/Co ), Co 3 O 4 -CeO 2 loading and reaction parameters on catalytic properties of the Co 3 O 4 -CeO 2 /AC catalysts were investigated. Various characterization techniques like scanning electron microscopy (SEM), X-ray diffraction (XRD) and H 2 temperature-programmed reduction (H 2 -TPR) were employed to reveal the relationship between catalysts nature and catalytic performance. Results illustrate that the supported Co 3 O 4 -CeO 2 catalyst on modified AC exhibits excellent catalytic properties, which highly depends on dispersity and reducibility of Co 3 O 4 affected by the time of support treatment ( t p ), calcination temperature, n Ce/Co and loading. The supported 35 wt% Co 3 O 4 -CeO 2 catalyst (1:8 of n Ce/Co ) on the modified AC with H 2 O 2 oxidation treatment for 6 h demonstrates the best catalytic properties and the almost complete CO transformation takes place in a wide temperature range of 125–190 °C. Moreover, it is also found that the developed catalyst exhibits an outstanding catalytic stability, and 100% CO conversion can be maintained as the time on stream evolutes up to 1800 min even in the presence of CO 2 and H 2 O in the feed. The optimized Co 3 O 4 -CeO 2 /AC may be a robust and promising catalyst for eliminating trace CO from H 2 -rich gases.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2018
·
IF 6.434
Guangjun Zhai,Jinguo Wang,Zimei Chen,Shuaifeng Yang,Yong Men
Three-dimensionally ordered macroporous (3DOM) Co 3 O 4 -CeO 2 catalysts with controllable Co/Ce molar ratios synthesized by colloidal crystal template method were developed to catalyze the NO x -assisted soot oxidation for the first time, and the obtained 3DOM Co 3 O 4 -CeO 2 catalysts exhibited highly enhanced soot oxidation activity. Detailed characterizations of 3DOM Co 3 O 4 -CeO 2 catalysts revealed that the highly enhanced soot oxidation activity was originated from the synergistic promoting effect by combining the macroporous effect resulted from the unique 3DOM framework, the chemical nature associated with more Co 3+ reactive sites, the surface enrichment of Ce species and the improved redox properties. Meanwhile, the high NO x storage and oxidation capacity resulted from the integrated respective merits of Co 3 O 4 and CeO 2 also accounted for the enhanced soot oxidation activity via NO x -assisted mechanism. Furthermore, the 3DOM Co 3 O 4 -CeO 2 catalysts demonstrated strong stability because of the surface enrichment of Ce species improving the thermal stability and the robust 3DOM framework inhibiting the structural collapse, showing their potential applications under practical conditions.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
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2024
·
IF 12.7
Dong Wang,Siping Ding,Zhenzhen He,Tonghui Zhang,Xuefen Wang
In this work, a novel Co 3 O 4 @CeO 2 nanofibrous membrane was prepared by the combination of interfacial defect engineering strategy and coaxial electrospinning for unusual levofloxacin degradation. Implanting active Co 3 O 4 into CeO 2 derived from Ce-UiO-66 created more oxygen vacancies and improved the interfacial interaction (electron transfer and specific surface area). In addition, accelerated redox recycling occurred on the catalyst surface because of the cooperation of Co sites and Ce sites. As a result, the optimal Co 3 O 4 @CeO 2 nanocomposite showed an unexpectedly improved degradation efficiency of levofloxacin with a rate constant higher than 6.9 times (CeO 2 ) and 2.6 times (Co 3 O 4 ), superior elimination (>98%) of antibiotic (norfloxacin, tetracycline and doxycycline hydrochloride) and dyes (methylene blue, rhodamine b, methyl orange and crystal violet). Moreover, C-type hollow structure nanofibers with increased reaction area were prepared by coaxial electrospinning to support nanoparticles for consecutive wastewater treatment. The prepared nanofibrous membrane with loading 50 wt% Co 3 O 4 @CeO 2 (PC50 NFMs) exhibited loose structure, resulting in 168.2 ± 12 L m −2 h −1 of permeability driven by gravity, while 164.2 L m −2 of levofloxacin was efficiently treated. Besides, the PC50 NFMs had satisfactory reusability and stability in real water bodies. This work paved a new avenue to control water pollution through the design of membranous catalysts.
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
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Shengjun Yi,Pincai Lai,Guilin Ma,Jinjian Pan,Zhen Chen,Yuanhang Qin,Xingmao Jiang
Nanocatalysis plays an important role in chemical industrial production, environmental protection and etc. However, traditional catalyst preparation methods are generally labor-intensive, time-consuming and need high-temperature calcination, which are not conducive to the preparation of nanostructured catalyst. Therefore, developing a green and facile method for nano-sized catalyst preparation is very significative. In this work, a series of nano-sized Co 3 O 4 /CeO 2 catalysts with high specific surface area, high oxygen storage and homogeneous distribution of active species were synthesized via a glucose-urea (G-U method), and applied in NO oxidation The NO oxidation performance indicates that the 12.5% CoCe G−U catalyst prepared by the G-U method shows higher activity than those of catalysts prepared by the traditional methods (precipitation, hydrothermal and impregnation methods). The characterization results revealed that the CoCe G−U catalysts have the highest specific surface area, pore volume, content of surface Ce 3+ and Co 3+ among the catalysts. Moreover, the nano Co 3 O 4 is better dispersed on CeO 2 , which resulted in more active oxygen species on the surface of the catalysts prepared by the G-U method. Herein, the higher specific surface area, the smaller Co 3 O 4 nanoparticles, the more active oxygen species and the higher Ce 3+ and Co 3+ contents of the CoCe G−U catalyst lead to the more excellent NO oxidation performance. This work provides a green and efficient approach for the industrial production of nano-sized oxide catalysts.
研究领域:
环境科学
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材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
·
IF 24.319
Shaomian Liu,Wenjuan Xue,Yongjun Ji,Wenqing Xu,Wenxing Chen,Lihua Jia,Tingyu Zhu,Ziyi Zhong,Guangwen Xu,Donghai Mei,Fabing Su
Simultaneously improving both NO x conversion and N 2 selectivity in the selective catalytic reduction of NO by CO (CO-SCR) under O 2 -containing conditions is highly challenging because of the competitive reactions of NO x and CO with O 2 . Here, we demonstrate that the interfacial oxygen vacancies (IOVs) generated at the Co 3 O 4 -CeO 2 heterointerfaces by ball-milling-induced strain can remarkably boost both NO x conversion and N 2 selectivity in the temperature range of 100–400 °C. The Co 3 O 4 -CeO 2 -IOV catalyst achieved approximately 100% NO x conversion and 100% N 2 selectivity (200–350 °C, 1–5 vol% O 2 , and 20,000 h −1 ); even under 10 vol% O 2 , it still showed good catalytic performance. The spectroscopy analysis and theoretical calculations reveal that compared with O 2 activation, IOVs are more favorable for the rate-limiting step of NO adsorption and dissociation. This work provides an effective strategy to create IOVs within metal oxide composite catalysts using ball-milling-induced interfacial strain for improving CO-SCR performance.
研究领域:
材料科学
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环境催化
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2024
·
IF 3.4
Ke Yang,Sisi Cheng,Ziqin Yao,Shijia Li,Yuting Yang
Researchers in the field of electrochemistry have recently become interested in the extraordinary features of ternary transition metal oxide nanostructures with spinel structure derived from metal-organic framework (MOFs). In this study, the zeolitic imidazolate framework (ZIF-67), which grows in situ on the surface of another metal organic framework (Ce-BTC), was created using the internal expansion growth method (IEGM), and the resulting complex was then used as a template to create the dumbbell-like nanocomposite. Due to the strong electron conduction of CeO 2 in composites, the electrode modified with composite material has good electrochemical activity in alkaline solution. As a glucose sensor, Co 3 O 4 /CeO 2 nanocomposite modified glass carbon electrode (Co 3 O 4 /CeO 2 /GCE) has better performance with a detection range of 83.75 μM–2796.84 μM, a reasonably good sensitivity of 790.746 μA mM −1 ·cm −2 , an estimated detection limit of 5.5 μA (S/N = 3) and a short response time less than 3s. The modified electrode can continue to function normally even when exposed to various interfering compounds for extended periods of time in the air. The successful use of this enzyme-free glucose sensor in fruit juice demonstrates its remarkable performance and provides ideas for future applications.
研究领域:
电化学
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材料科学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Zhen Cheng,Zhu Chen,Jingrong Li,Shufeng Zuo,Peng Yang
Mesoporous silica-pillared clay (SPC) was synthesized by a soft template method. Compared with the raw montmorillonite (MMT), the basal spacing of SPC increased from 0.96 to 2.61 nm, the specific surface area increased from 30 to 453 m 2 /g, and the thermal stability was also improved, all of which could reduce the mass transfer resistance and improve the adsorption capacity of toluene. SPC supported Co 3 O 4 and rare earth (Y, La, Ce, Pr and Nd) nano-composite catalysts were prepared by a deposition-precipitation method. Among them, 10% Co-5% Ce/SPC displayed the highest catalytic combustion activity, and the reaction temperature for toluene combustion was about 200 °C (98% conversion). This catalyst displayed good durability, and conversion of toluene dropped slightly from 96% to 90% in 1000 h continuous reaction at 190 °C. Co 3 O 4 and CeO 2 had particle sizes of 5–8 nm and were dispersed homogeneously on the surface of SPC. Introduction of CeO 2 enhanced oxygen storage/transport capacity, and improved the dispersion of Co 3 O 4 on SPC. The interaction of Co 3 O 4 -CeO 2 and SPC, the co-existence of Co 2+ /Co 3+ and the higher concentration of Ce 3+ ions on the catalyst surface contribute to the high catalytic oxidative activity of 10% Co-5% Ce/SPC for toluene combustion.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
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2023
·Vol. 40
·期 12
·3059-3067
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IF 2.7
Yin Zihang,He Ruibo,Nie Fei,Wei Zhen,Jia Bo,Feng Qing,Fu Xiaolong,Zhang Wenyan
The oxygen evolution kinetics of industrial copper electrodeposition is slow, resulting in low electrocatalytic activity and high energy consumption. In this work, a quaternary composite of carbon coated active particles containing Mn, Co and Ce were prepared (Mn-Co 3 O 4 /CeO 2 @C), and Ti/Sb-SnO 2 /PbO 2 electrode doped with these active particles was prepared by co-electrodeposition. The microstructure and chemical composition of the electrode was characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffractometry (XRD). Linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and Tafel polarization curve (Tafel) were used to study the electrochemical properties of anode materials. The results showed that the doping of Mn-Co 3 O 4 /CeO 2 @C active particles promoted the crystal transition of PbO 2 , decreased the average grain size, and the doping of Ce increases the average valence state of Co. The modified titanium electrode showed excellent catalytic activity of the oxygen evolution reaction (OER) characteristics. The overpotential of the doped Ti/Sb-SnO 2 /PbO 2 anode was only 453 mV when the current density was 20 mA cm −2 in 0.5 M H 2 SO 4 solution, which is 508 mV lower than that of the undoped Ti/Sb-SnO 2 /PbO 2 anode. In simulated copper electro-deposition experiments, the cell voltage was reduced by about 400 mV, compared to the undoped Ti/Sb-SnO 2 /PbO 2 electrode.
研究领域:
材料科学
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电化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2019
·
IF 7.65
Wei Li,Yuxin Li,Deyun Zhang,Yeqing Lan,Jing Guo
CuO-Co 3 O 4 @CeO 2 nanoparticles used as a heterogeneous catalyst were prepared via a sol-gel method and characterized by various techniques. For comparison, a series of oxides was investigated for activating peroxymonosulfate (PMS) during the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). The results indicated that CuO-Co 3 O 4 @CeO 2 exhibited the highest catalytic performance among the catalysts. Complete degradation of 2,4-D (20 mg/L) was realized within 45 min at 1 mM PMS, CuO-Co 3 O 4 @CeO 2 loading of 0.07 g/L, and pH of 6. Recycling experiments confirmed that CuO-Co 3 O 4 @CeO 2 was very stable, and the 2,4-D degradation efficiencies ranged from 100% to 97.5%, decreasing by only 2.5% after the fifth run. The outstanding catalysis of CuO-Co 3 O 4 @CeO 2 resulted from the synergy of cerium, cobalt, and copper. Electron paramagnetic resonance and radical scavenger experiments confirmed the production of SO 4 • − and • OH radicals in the CuO-Co 3 O 4 @CeO 2 /PMS system, which were responsible for efficient decomposition of 2,4-D. Furthermore, the combination of CuO-Co 3 O 4 @CeO 2 andPMS was applied to treat natural water containing 2,4-D, and a high 2,4-D removal rate was also achieved. Based on these results, it was deduced that CuO-Co 3 O 4 @CeO 2 can be utilized as a catalyst to activate PMS and destroy organic contaminants in aqueous solution.
研究领域:
环境科学
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催化
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水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2017
·
IF 4.421
Ping Yang,Yunshi Liu
Co 3 O 4 nanochain and Co 3 O 4 /CeO 2 heterostructures were prepared via an electrospinning process and subsequent calcination . The formation and shape evolution from Co 3 O 4 nanochains to Co 3 O 4 /CeO 2 composite nanobelts were investigated, suggesting that both components and preparation parameters play important roles in resulted morphology and properties. Homogeneous Co 3 O 4 /CeO 2 junctions in belt samples were formed towards enhanced catalysis performance. Well-dispersed Au nanoparticles were deposited on Co 3 O 4 /CeO 2 composite nanostructures or doped inside through reduction and direct calcination route method, respectively. The loading of Au nanoparticles significantly enhanced catalytic performance with onset CO conversion at 100 °C and resulted in CO conversion over at 127 °C.
研究领域:
材料科学
·
催化化学
✓ 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）