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期刊论文 37

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Influence of crystalline phase of Li-Al-O oxides on the activity of Wacker-type catalysts in dimethyl

Yadong GE, Yuanyuan DONG, Shengping WANG, Yujun ZHAO, Jing LV, Xinbin MA

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 415-422 doi: 10.1007/s11705-012-1214-4

摘要： The catalysts supported on LiAl O (spinel) for vapor phase synthesis of dimethyl carbonate (DMC) from methyl nitrite (MN) have been studied. Their catalytic activities on supports prepared by different methods were evaluated in a continuous reactor. The samples were characterized by powder X-ray diffraction, N adsorption-desorption isotherms, fourier transform infrared spectroscopy and temperature-programmed reduction of H . Li/Al molar ratio and calcination temperature greatly influence the structure of crystalline phase of Li-Al-O oxides. Desirable LiAl O (spinel) was formed at 800°C, while LiAl O (primitive cube) formed at 900°C is undesirable for the reaction. A high Li/Al molar ratio, which was related with LiAlO , also slowed the reaction rate. The electron transfer ability and the interaction with active component are the important properties of the spinel-based supports. The CuCl -PdCl /LiAl O (spinel) with better electron transfer ability and low Pd reduction temperature exhibited a better catalytic ability.

关键词： Wacker-type catalyst     dimethyl carbonate     methyl nitrite     spinel    

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NiBO (B = Mn or Co) catalysts for NH-SCR of NO at low-temperature in microwave field

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1696-y

摘要：

● Microwave-assisted catalytic NH3-SCR reaction over spinel oxides is carried out.

关键词： Microwave field     Spinel oxides     NOx     Selective catalytic reduction    

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Efficient conversion of lignin to alkylphenols over highly stable inverse spinel MnFeO catalysts

《化学科学与工程前沿（英文）》 2023年 第17卷 第8期   页码 1085-1095 doi: 10.1007/s11705-022-2236-1

摘要： The aromatic properties of lignin make it a promising source of valuable chemicals and fuels. Developing efficient and stable catalysts to effectively convert lignin into high-value chemicals is challenging. In this work, MnFe2O4 spinel catalysts with oxygen-rich vacancies and porous distribution were synthesized by a simple solvothermal process and used to catalyze the depolymerization of lignin in an isopropanol solvent system. The specific surface area was 110.5 m2∙g–1, which substantially increased the active sites for lignin depolymerization compared to Fe3O4. The conversion of lignin reached 94%, and the selectivity of alkylphenols exceeded 90% after 5 h at 250 °C. Underpinned by characterizations, products, and density functional theory analysis, the results showed that the catalytic performance of MnFe2O4 was attributed to the composition of Mn and Fe with strong Mn–O–Fe synergy. In addition, the cycling experiments and characterization showed that the depolymerized lignin on MnFe2O4 has excellent cycling stability. Thus, our work provides valuable insights into the mechanism of lignin catalytic depolymerization and paves the way for the industrial-scale application of this process.

关键词： lignin depolymerization     spinel     catalysts     hydrogenation    

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Influences of spinel type and polymeric surfactants on the size evolution of colloidal magnetic nanocrystals

Tahereh R. BASTAMI,Mohammad H. ENTEZARI,Chiwai KWONG,Shizhang QIAO

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 378-385 doi: 10.1007/s11705-014-1441-y

摘要： Two types of polymeric surfactants, PEG and PVP , were used for the preparation of magnetic ferrite MFe O (M= Mn, Fe) colloidal nanocrystals using a solvothermal reaction method. The effect of spinel type effect on the size evolution of various nanoparticles was investigated. It was found that Fe O nanoparticles exhibited higher crystalinity and size evolution than MnFe O nanoparticles with use of the two surfactants. It is proposed that this observation is due to fewer tendencies of surfactants on the surface of Fe O building blocks nanoparticles than MnFe O . Less amounts of surfactant or capping agent on the surface of nanoparticles lead to the higher crystalibity and larger size. It is also suggested that the type of spinel (normal or inverted spinel) plays a key role on the affinity of the polymeric surfactant on the surface of building blocks.

关键词： spinel type     polymeric surfactant     size evolution     mangnetic ferrite nanoparticle    

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Catalytic combustion of volatile organic compounds using perovskite oxides catalysts—a review

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1649-1676 doi: 10.1007/s11705-023-2324-x

摘要： With the rapid development of industry, volatile organic compounds (VOCs) are gaining attention as a class of pollutants that need to be eliminated due to their adverse effects on the environment and human health. Catalytic combustion is the most popular technology used for the removal of VOCs as it can be adapted to different organic emissions under mild conditions. This review first introduces the hazards of VOCs, their treatment technologies, and summarizes the treatment mechanism issues. Next, the characteristics and catalytic performance of perovskite oxides as catalysts for VOC removal are expounded, with a special focus on lattice distortions and surface defects caused by metal doping and surface modifications, and on the treatment of different VOCs. The challenges and the prospects regarding the design of perovskite oxides catalysts for the catalytic combustion of VOCs are also discussed. This review provides a reference base for improving the performance of perovskite catalysts to treat VOCs.

关键词： perovskite oxides     volatile organic compounds     catalytic combustion     reaction mechanism    

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Multivalent manganese oxides with high electrocatalytic activity for oxygen reduction reaction

Xiangfeng Peng, Zhenhai Wang, Zhao Wang, Yunxiang Pan

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 790-797 doi: 10.1007/s11705-018-1706-y

摘要： A noble-metal-free catalyst based on both Mn O and MnO was prepared by using the dielectric barrier discharge technique at moderate temperature. The prepared catalyst shows a higher electrocatalytic activity towards the oxygen reduction reaction than the catalyst prepared by using the traditional calcination process. The enhanced activity could be due to the coexistence of manganese ions with different valences, the higher oxygen adsorption capacity, and the suppressed aggregation of the catalyst nanoparticles at moderate temperature. The present work would open a new way to prepare low-cost and noble-metal-free catalysts at moderate temperature for more efficient electrocatalysis.

关键词： oxygen reduction reaction     manganese oxides     mixed valences of manganese     oxygen adsorption     dielectric barrier discharge    

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Redox reactions of iron and manganese oxides in complex systems

Jianzhi Huang, Huichun Zhang

《环境科学与工程前沿（英文）》 2020年 第14卷 第5期 doi: 10.1007/s11783-020-1255-8

摘要： • Mechanisms of redox reactions of Fe- and Mn-oxides were discussed. • Oxidative reactions of Mn- and Fe-oxides in complex systems were reviewed. • Reductive reaction of Fe(II)/iron oxides in complex systems was examined. • Future research on examining the redox reactivity in complex systems was suggested. Conspectus Redox reactions of Fe- and Mn-oxides play important roles in the fate and transformation of many contaminants in natural environments. Due to experimental and analytical challenges associated with complex environments, there has been a limited understanding of the reaction kinetics and mechanisms in actual environmental systems, and most of the studies so far have only focused on simple model systems. To bridge the gap between simple model systems and complex environmental systems, it is necessary to increase the complexity of model systems and examine both the involved interaction mechanisms and how the interactions affected contaminant transformation. In this Account, we primarily focused on (1) the oxidative reactivity of Mn- and Fe-oxides and (2) the reductive reactivity of Fe(II)/iron oxides in complex model systems toward contaminant degradation. The effects of common metal ions such as Mn2+ , Ca2+, Ni2+, Cr3+ and Cu2+, ligands such as small anionic ligands and natural organic matter (NOM), and second metal oxides such as Al, Si and Ti oxides on the redox reactivity of the systems are briefly summarized.

关键词： Iron oxides     manganese oxides     reduction     oxidation     complex systems     reaction kinetics and mechanisms    

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The role of manganese oxides in the activation of peroxymonosulfate (PMS)

Jianzhi Huang, Huichun Zhang

《环境科学与工程前沿（英文）》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1158-8

摘要： Manganese oxides (MnOx) have been demonstrated to be effective materials to activate Oxone (i.e., PMS) to degrade various contaminants. However, the contribution of direct oxidation by MnOx to the total contaminant degradation under acidic conditions was often neglected in the published work, which has resulted in different and even conflicting interpretations of the reaction mechanisms. Here, the role of MnOx (as both oxidants and catalysts) in the activation of Oxone was briefly discussed. The findings offered new insights into the reaction mechanisms in PMS-MnOx and provided a more accurate approach to examine contaminant degradation for water/wastewater treatment.

关键词： Peroxymonosulfate     Manganese oxides     Catalyst     Oxidant    

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Review on research and application of mesoporous transitional metal oxides in water treatment

Minghao SUI, Lei SHE

《环境科学与工程前沿（英文）》 2013年 第7卷 第6期   页码 795-802 doi: 10.1007/s11783-013-0521-4

摘要： This paper reviews the application of mesoporous transitional metal oxides in water treatment on basis of the catalysis and adsorption. Mesoporous transitional metal oxides are characterized by their intrinsic features, such as a high surface area, a highly ordered array of unidimensional pores with a very narrow pore size distribution, and highly dispersed active sites. Finally, the suggestions of further study on application are proposed.

关键词： mesoporous materials     transitional metal oxides     catalysis     adsorption     water treatment    

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A mini-review of ferrites-based photocatalyst on application of hydrogen production

《能源前沿（英文）》 2021年 第15卷 第3期   页码 621-630 doi: 10.1007/s11708-021-0761-0

摘要： Photocatalytic water splitting for hydrogen production is a promising strategy to produce renewable energy and decrease production cost. Spinel-ferrites are potential photocatalysts in photocatalytic reaction system due to their room temperature magnetization, the high thermal and chemical stability, narrow bandgap with broader visible light absorption, and proper conduction band energy level with strong oxidation activity for water or organic compounds. However, the fast recombination of the photoexcited electrons and holes is a critical drawback of ferrites. Therefore, the features of crystallinity, particle size, specific surface area, morphology, and band energy structure have been summarized and investigated to solve this issue. Moreover, composites construction with ferrites and the popular support of TiO2 or g-C3N4 are also summarized to illustrate the advanced improvement in photocatalytic hydrogen production. It has been shown that ferrites could induce the formation of metal ions impurity energy levels in TiO2, and the strong oxidation activity of ferrites could accelerate the oxidation reaction kinetics in both TiO2/ferrites and g-C3N4/ferrites systems. Furthermore, two representative reports of CaFe2O4/MgFe2O4 composite and ZnFe2O4/CdS composite are used to show the efficient heterojunction in a ferrite/ferrite composite and the ability of resistance to photo-corrosion, respectively.

关键词： photocatalyst     spinel-ferrite     composite     photocatalytic hydrogen production    

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Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1211-1223 doi: 10.1007/s11705-022-2145-3

摘要： The one-step highly selective oxidation of cyclohexane into cyclohexanone and cyclohexanol as the essential intermediates of nylon-6 and nylon-66 is considerably challenging. Therefore, an efficient and low-cost catalyst must be urgently developed to improve the efficiency of this process. In this study, a Co3O4–CeO2 composite oxide catalyst was successfully prepared through ultrasound-assisted co-precipitation. This catalyst exhibited a higher selectivity to KA-oil, which was benefited from the synergistic effects between Co3+/Co2+ and Ce4+/Ce3+ redox pairs, than bulk CeO2 and/or Co3O4. Under the optimum reaction conditions, 89.6% selectivity to KA-oil with a cyclohexane conversion of 5.8% was achieved over Co3O4–CeO2. Its catalytic performance remained unchanged after five runs. Using the synergistic effects between the redox pairs of different transition metals, this study provides a feasible strategy to design high-performance catalysts for the selective oxidation of alkanes.

关键词： Co3O4–CeO2 composite oxides     cyclohexanone     cyclohexanol     ultrasonic-assisted co-precipitation     selective oxidation     solvent-free    

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Fluoride ions adsorption from water by CaCO enhanced Mn–Fe mixed metal oxides

《化学科学与工程前沿（英文）》 2023年 第17卷 第2期   页码 236-248 doi: 10.1007/s11705-022-2193-8

摘要： Novel CaCO3-enhanced Mn–Fe mixed metal oxides (CMFC) were successfully prepared for the first time by a simple-green hydrothermal strategy without any surfactant or template combined with calcination process. These oxides were then employed as an adsorbent for adsorptive removal of excess fluoride ions. The adsorbent was characterized by SEM, XPS, XRD, FTIR, and BET analysis techniques. The adsorption property of CMFC toward fluoride ion was analyzed by batch experiments. In fact, CMFC exhibited adsorption capacity of 227.3 mg∙g‒1 toward fluoride ion. Results showed that ion exchange, electrostatic attraction and chemical adsorption were the main mechanism for the adhesion of large amount of fluoride ion on the CMFC surface, and the high adsorption capacity responded to the low pH of the adsorption system. When the fluoride ion concentration was increased from 20 to 200 mg∙L‒1, Langmuir model was more in line with experimental results. The change of fluoride ion adsorption with respect to time was accurately described by pseudo-second-order kinetics. After five cycles of use, the adsorbent still maintains a performance of 70.6% of efficiency, compared to the fresh adsorbent. Therefore, this material may act as a potential candidate for adsorbent with broad range of application prospects.

关键词： mesoporous materials     metal oxides     fluoride ion     adsorption mechanism    

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Application of metal oxides-based nanofluids in PV/T systems: a review

《能源前沿（英文）》 2022年 第16卷 第3期   页码 397-428 doi: 10.1007/s11708-021-0758-8

摘要： Having the wide application of metal oxides in energy technologies, in recent years, many researchers tried to increase the performance of the PV/T system by using metal oxide-based nanofluids (NFs) as coolants or optical filters or both at the same time. This paper summarizes recent research activities on various metal oxides (Al2O3, TiO2, SiO2, Fe3O4, CuO, ZnO, MgO)-based NFs performance in the PV/T system regarding different significant parameters, e.g., thermal conductivity, volume fraction, mass flowrate, electrical, thermal and overall efficiency, etc. By conducting a comparative study among the metal oxide-based NFs, Al2O3/SiO2-water NFs are mostly used to achieve maximum performance. The Al2O3-water NF has a prominent heat transfer feature with a maximum electrical efficiency of 17%, and a maximum temperature reduction of PV module of up to 36.9°C can be achieved by using the Al2O3-water NF as a coolant. Additionally, studies suggest that the PV cell’s efficiency of up to 30% can be enhanced by using a solar tracking system. Besides, TiO2-water NFs have been proved to have the highest thermal efficiency of 86% in the PV/T system, but TiO2 nanoparticles could be hazardous for human health. As a spectral filter, SiO2-water NF at a size of 5 nm and a volume fraction of 2% seems to be very favorable for PV/T systems. Studies show that the combined use of NFs as coolants and spectral filters in the PV/T system could provide a higher overall efficiency at a cheaper rate. Finally, the opportunities and challenges of using NFs in PV/T systems are also discussed.

关键词： metal oxide     nanofluids (NFs)     nanoparticles (NPs)     optical filter     PV/T systems     solar energy    

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Crystalline mesoporous transition metal oxides: hard-templating synthesis and application in environmental

Zhen MA, Bei ZHOU, Yu REN

《环境科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 341-355 doi: 10.1007/s11783-012-0472-1

摘要： Mesoporous silicas such as MCM-41 and SBA-15 possess high surface areas, ordered nanopores, and excellent thermal stability, and have been often used as catalyst supports. Although mesoporous metal oxides have lower surface areas compared to mesoporous silicas, they generally have more diversified functionalities. Mesoporous metal oxides can be synthesized via a soft-templating or hard-templating approach, and these materials have recently found some applications in environmental catalysis, such as CO oxidation, N O decomposition, and elimination of organic pollutants. In this review, we summarize the synthesis of mesoporous transition metal oxides using mesoporous silicas as hard templates, highlight the application of these materials in environmental catalysis, and furnish some prospects for future development.

关键词： mesoporous materials     silica     metal oxide     hard-templating     environmental catalysis    

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Promotion of transition metal oxides on the NH

Weiman Li, Haidi Liu, Yunfa Chen

《环境科学与工程前沿（英文）》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0914-x

摘要： Manganese and chromium oxides promote the NH -SCR activity of Zr-Ce mixed oxide. Cr-Zr-Ce mixed oxide exhibited>80% NO conversion at a wide temperature window. More acid sites and higher reducibility may responsible for the high SCR ability. Chromium oxide and manganese oxide promoted ZrO -CeO catalysts were prepared by a homogeneous precipitation method for the selective catalytic reduction of NO with NH . A series of characterization including X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Brunauer–Emmett–Teller (BET) surface area analysis, H temperature-programmed reduction (H -TPR), and X-ray photoelectron spectroscopy (XPS) were used to evaluate the influence of the physicochemical properties on NH -SCR activity. Cr-Zr-Ce and Mn-Zr-Ce catalysts are much more active than ZrO -CeO binary oxide for the low temperature NH -SCR, mainly because of the high specific surface area, more surface oxygen species, improved reducibility derived from synergistic effect among different elements. Mn-Zr-Ce catalyst exhibited high tolerance to SO and H O. Cr-Zr-Ce mixed oxide exhibited>80% NO conversion at a wide temperature window of 100°C–300°C. DRIFT studies showed that the addition of Cr is beneficial to the formation of Bronsted acid sites and prevents the formation of stable nitrate species because of the presence of Cr . The present mixed oxide can be a candidate for the low temperature abatement of NO .

关键词： NH3-selective catalytic reduction     NOx     Low temperature     Cr-Zr-Ce    

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标题 作者 时间 类型 操作

Influence of crystalline phase of Li-Al-O oxides on the activity of Wacker-type catalysts in dimethyl

Yadong GE, Yuanyuan DONG, Shengping WANG, Yujun ZHAO, Jing LV, Xinbin MA

期刊论文

NiBO (B = Mn or Co) catalysts for NH-SCR of NO at low-temperature in microwave field

期刊论文

Efficient conversion of lignin to alkylphenols over highly stable inverse spinel MnFeO catalysts

期刊论文

Influences of spinel type and polymeric surfactants on the size evolution of colloidal magnetic nanocrystals

Tahereh R. BASTAMI,Mohammad H. ENTEZARI,Chiwai KWONG,Shizhang QIAO

期刊论文

Catalytic combustion of volatile organic compounds using perovskite oxides catalysts—a review

期刊论文

Multivalent manganese oxides with high electrocatalytic activity for oxygen reduction reaction

Xiangfeng Peng, Zhenhai Wang, Zhao Wang, Yunxiang Pan

期刊论文

Redox reactions of iron and manganese oxides in complex systems

Jianzhi Huang, Huichun Zhang

期刊论文

The role of manganese oxides in the activation of peroxymonosulfate (PMS)

Jianzhi Huang, Huichun Zhang

期刊论文

Review on research and application of mesoporous transitional metal oxides in water treatment

Minghao SUI, Lei SHE

期刊论文

A mini-review of ferrites-based photocatalyst on application of hydrogen production

期刊论文

Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective

期刊论文

Fluoride ions adsorption from water by CaCO enhanced Mn–Fe mixed metal oxides

期刊论文

Application of metal oxides-based nanofluids in PV/T systems: a review

期刊论文

Crystalline mesoporous transition metal oxides: hard-templating synthesis and application in environmental

Zhen MA, Bei ZHOU, Yu REN

期刊论文

Promotion of transition metal oxides on the NH

Weiman Li, Haidi Liu, Yunfa Chen

期刊论文