Molecular Catalysis
·
2024
·
IF 3.9
Dongyang Yang,Bingxiao Feng,Hongxin Wang,Qingjuan Xie,Yaping Liu,Hengjun Gai,Hongbing Song
Selective oxidation of alcohols to aldehydes by molecular oxygen is one of the most important transformations in multiphase catalysis. In this paper, a catalyst with selective oxidation ability was designed and synthesized for the selective catalytic oxidation of benzyl alcohol. N-doped carbon materials were prepared by high-temperature calcination using hydrothermal reaction products of citric acid and melamine as a carbon source, and a bimetallic catalyst supported by Ru-CeO 2 was constructed using the mixture as the carrier for the selective oxidation of benzyl alcohol to benzaldehyde. The results showed that the introduction of CeO 2 could effectively improve the oxidizing ability and catalytic activity of the catalyst. The Ru-Ce 0.05 /NC170–600 catalyst was able to convert 85.5 % benzyl alcohol into benzaldehyde at 140 °C, 6 h, and 2 MPa, and the selectivity for benzaldehyde was 100 %. It was demonstrated by DFT that it was theoretically feasible to generate benzaldehyde by extracting hydrogen atoms from benzyl alcohol molecules. Further, the selective oxidation experiments on other alcohols showed that the catalyst has high activity for the oxidation of various alcohols to generate the corresponding carbonyl products, and it is a catalyst with broad-spectrum selective oxidation ability. In this study, a green synthesis route of benzaldehyde was proposed to solve the problems in the traditional process. Meanwhile, it provides a new idea for the synthesis of carbonyl products by selective oxidation of alcohols.
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
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Lulu Guo,Mengmeng Liu,Xuguang Zhang,Taotao Sui
The development of feasible and facile method to construct oxygen vacancies on metal oxides is crucial for improving their gas sensing properties. In this work, we developed a highly sensitive and stable CO gas sensor based on metal-organic frameworks (MOFs) template-derived Pt nanoparticles (NPs)-functionalized CeO 2 nanorods (Pt-CeO 2 ) with abundant oxygen vacancies through facile solvothermal method. The obtained Pt-CeO 2 -based sensors exhibit good thermal stability and superior CO sensing performance with high response value of 47.7% towards 500 ppm CO at 300 °C, which is higher than that of the pristine CeO 2 sensor (17.8%). Moreover, Pt-CeO 2 -based sensor exhibits excellent selectivity, rapid response/recovery speed (9/11 s) and remarkable long-term stability toward CO. Finally, the enhanced CO sensing mechanism is proposed through a combination of experiments and characterizations, which is attributed to porous structure, abundant oxygen vacancies and electron sensitization effect of Pt NPs. This work not only provides unique insights into the facile design of metal oxide-based nanomaterials with abundant oxygen vacancies, but also has great application potential in building sensing systems for fast CO detection.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
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IF 3.83
Xiaoyu Yang,Xuanxuan Lei,Shaokun Tang
A simple hydrothermal method is utilized to fabricate hierarchically olive-like γ -Al 2 O 3 using ionic liquid [Bmim]BF 4 as the structure directing agent . The olive-like γ -Al 2 O 3 presents uniform morphology with the average diameter of 500 nm and rich mesopores. As template, ionic liquid [Bmim]BF 4 plays a crucial role in the controllable morphology of the product. [Bmim]BF 4 is absorbed on the AlOOH nanoparticles surface via the H-bond interaction and induces crystalline oriented growth. Then the forming AlOOH nanosheets self-assemble into olive-like hierarchical structure through π–π stack interaction. Given that the structure advantage of the olive-like γ-Al 2 O 3 and the limited study concerning cerium-based catalysts in Fenton-like reaction, nano-CeO 2 / γ -Al 2 O 3 supported catalyst is prepared and used in Fenton-like degradation for the first time. The result suggests that the olive-like γ -Al 2 O 3 support not only reduces the surface energy with more uniform CeO 2 (ca. 4–5 nm) dispersion but also improve the concentration of Ce 3+ active sites. The CeO 2 / γ -Al 2 O 3 catalyst displays superior catalytic activity for the degradation of Orange II (AO7) compared with pure CeO 2 nanoparticles.
研究领域:
材料科学
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环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2024
·Vol. 38
·期 8
·e7556
·
IF 3.7
Muhammad Jawad Ahmad,Xue Lu,Liye Liang,Guangming Li
Since catalytic chemoselective reduction of corresponding nitroarenes is a significant route to produce functionalized anilines, developing inexpensive and highly active catalyst is imperia. Herein, the Co-Ce-H 2 salen-hmta composite was first prepared by grinded completely the mixture of Co-H 2 Salen and hexamethylenetetramine (hmta) in 1:1 mol ratio in a mortar. The 3d–4f hetero-metal Co-Ce-H 2 salen coordination polymer acted as a support precursor and hmta provided the nitrogen source. Then, a target catalyst of Co/NC-CeO 2 -hmta were afforded by pyrolysis of Co-Ce-H 2 salen-hmta composite at 800°C in the presence of argon atmosphere. When the target catalyst of Co/NC-CeO 2 -hmta and reference catalysts were applied for the hydrogenation of nitroarenes under N 2 H 4 , the target catalyst of Co/NC-CeO 2 -hmta exhibited better performance than reference catalysts in terms of conversion, yield, selectivity, and recyclability. Spectral analysis suggested that the high catalytic performance of a target catalyst of Co/NC-CeO 2 -hmta were attributed to highly dispersed metallic Co 0 , rich oxygen vacancies, and nitrogen-doped carbon matrix.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Junkai Hao,Jing Feng,Shuo Sun,Zhongxiang Cao,Wenjing Xu,Lei Hu,Wenli Yao,Zhengquan Yan
To reliably monitor dopamine (DA), a common neurotransmitter, a kind of nano CeO 2 /CuO modified carboxylated chitosan nanozyme (CeO 2 /CuO@CC) was constructed under microwave-assisted conditions. The proposed CeO 2 /CuO@CC exhibited superior synergistic- enhancement oxidase-like activity, with high specific surface area and superior stability. It could accelerate the oxidization of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into blue oxTMB in the air. What’s more, the presence of trace DA could exclusively change the enzyme-like activity of CeO 2 /CuO@CC, accompanied with visual color changes from blue to colorless. Under the optimized conditions, there expressed double ratiometric linear relationships between lg( A 652 / A 285 )/lg( A 370/ A 285 ) and c DA , with a large linear range between 6.0 × 10 −9 and 1.0 × 10 −5 M of DA. When applied for visual detection of DA in real samples, the detection limit was low to 2.0 × 10 −9 M with RSD % less than 4.14 %. The mechanisms for enhanced oxidase-mimic activity of CeO 2 /CuO@CC and its selective detection of DA were proposed. This work will offer an insight to design efficient nanozyme for visual detection of bio-analytes in practice.
研究领域:
生物化学
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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 CATALYSIS B-ENVIRONMENTAL
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2017
·
IF 9.446
Hui He,Xueting Lin,Shujun Li,Zeng Wu,Jingheng Gao,Junliang Wu,William Wen,Daiqi Ye,Mingli Fu
Surface species and oxygen vacancies were studied in MnO x (0.4)-CeO 2 toward repeated soot oxidation. MnO x (0.4)-CeO 2 catalysts prepared by the citric acid complex method were repeatedly used in a 10% O 2 /Ar gas flow and showed favorable activity and satisfactory durability toward soot oxidation. X-ray diffraction (XRD), N 2 adsorption/desorption, Electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS) and in situ visible/UV Raman characterization methods were utilized to investigate the structural features of fresh and reused catalysts. The irreversible conversion of high valence manganese species as well as the reduction of Frenkel-type oxygen vacancies and lattice oxygen could be clearly observed in the reused samples, which were associated with the slight deactivation. Spectators and participators were two existing forms of Frenkel-type oxygen vacancies. It was noteworthy that the participators almost fully regenerated after each reaction cycle, which ensured the ability to activate O latt in repeated soot oxidation process. Therefore, the catalysts maintained favorable activity and satisfactory durability, which was mainly because the relatively stable level of participators.
研究领域:
催化化学
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环境催化
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材料化学
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表面科学
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能源化学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
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2015
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IF 2.79
Shangzhe Sun,Ming Zhao,Liang Cai,Shuai Zhang,Dewang Zeng,Rui Xiao
The iron-based oxygen carrier with high oxygen transfer capacity has always been the key point in the chemical looping hydrogen generation (CLHG) process. In this study, CeO2-modified iron-based oxygen carriers with the porous reticular structure were prepared by the sol–gel method. Samples were tested in a thermogravimetric analyzer (TGA) and lab-scale fixed-bed reactor, respectively, to evaluate their capacities of hydrogen production and the resistance to carbon deposition or Fe3C formation. The effects of preparation conditions (CeO2 loading and [C6H8O7·H2O]/[PEG400] molar ratio) and experimental conditions (reducing atmosphere and temperature) on the physicochemical properties of CeO2-modified iron-based oxygen carriers were investigated. The initial screening test in TGA was done to select the samples with excellent reducibility and strong resistance to carbon deposition or Fe3C formation. Subsequent tests in the fixed-bed reactor were conducted to evaluate the redox characteristics and cyclic performance of the selected CeO2-modified samples. The results confirmed that iron-based oxygen carriers modified by CeO2 could effectively inhibit carbon deposition or Fe3C formation and the oxygen carrier prepared under the preparation conditions of Fe2O3/CeO2/Al2O3 = 65/5/30 and C6H8O7·H2O/PEG400 = 3 stood out from all the candidates by virtue of its high hydrogen production efficiency and the excellent recycle ability in the CLHG process. The oxygen carriers at the optimal reducing atmosphere (CO/H2/N2 = 40/30/30 and the steam oxidation reaction at 900 °C) showed the best performance with the highest hydrogen yield.
研究领域:
能源材料
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Luxia Yin,Jiacheng Xu,Bo Zhang,Leigang Wang,Wanyi Tao,Xiao Teng,Wensheng Ning,Zekai Zhang
A simple, low energy consumption and environment-friendly strategy was used to prepare highly dispersed CeO 2 /SiO 2 aerogel composites with different molar ratio of Si/Ce via sol-gel method and subsequently drying under the ambient pressure, in which the oxidation of Ce 3+ species into Ce 4+ species could be achieved by adding H 2 O 2 . The structural and surface properties of adsorbents were analyzed by XPS, XRD, FT-IR, Py-IR, SEM, XRF and N 2 adsorption-desorption isotherm. The adsorption desulfurization performances of CeO 2 /SiO 2 for thiophenic compounds from simulated gasoline and model aromatic products were investigated and compared by the breakthrough and batch adsorption experiments. As a result, the weak Lewis acid centers appeared on the surface of CeO 2 /SiO 2 . Among them, CeO 2 /SiO 2 with a Si/Ce of 25 performed best, the adsd by Duanpacity for TP from simulated gasoline (n-heptane) was 10.9 mg-S/g ads , followed by model aromatic products (benzene, 10.6 mg-S/g ads ; p-xylene, 10.1 mg-S/g ads ), however, the difference between them was slight, attributed to the formation of S-Ce bonding instead of C-Ce bonding. The very weak competitive adsorption of benzene and p-xylene with thiophene originated from the weak Lewis acid-base interaction. After the fourth solvent washing regeneration, the breakthrough adsorption capacity of regenerated CeO 2 /SiO 2 -25 still remained 60% of the fresh one. The equilibrium adsorption data of CeO 2 /SiO 2 -25 for thiophene were well fitted by Langmuir and Freundlich model, and the adsorption for TP was more favorable at the higher temperature. The adsorption process of CeO 2 /SiO 2 -25 was well fitted by pseudo-second-order kinetic model, which was spontaneous, endothermic and the freedom degree increased. The solvent (n-heptane, benzene, p-xylene) hardly influence the adsorption behavior of TP on CeO 2 /SiO 2 .
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Jun Zhao,Jun Tang,Tinghui Dang
Interaction with soil mineral particles (SMPs) and organic matters can significantly determine the fate of nanoparticles (NPs) in the environment such as waters, sediments, and soils. In this study, the heteroaggregation of CeO 2 NPs with different soil minerals (kaolinite, montmorillonite , goethite and hematite) and the influence of extracellular polymeric substance (EPS) were studied. The obvious heteroaggregation between CeO 2 NPs with different SMPs were demonstrated via co-settling and aggregation kinetics experiments. The variety in the heteroaggregation between CeO 2 NPs with different SMPs is mainly induced by the difference in their surface properties, such as surface charge, specific surface areas and surface complexation. The presence of EPS can result in great inhibition on the heteroaggregation between CeO 2 NPs with the positive charged goethite by enhancing the electrostatic repulsion between NPs and mineral colloids. However, the influence of EPS on the interaction between CeO 2 NPs with negative charged SMPs is more dependent on the steric stabilization. The presence of EPS may promote the migration of CeO 2 NPs in environment and then increase their risks to human health and ecosystems. These findings contribute to better understanding interactions between NPs and SMPs and have important implications on predicting the behaviors and risks of NPs in the natural environment.
研究领域:
环境科学
·
纳米生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Zhuoqun Deng,Nianxi Wang,Yang Wang,Xujing Li,Haixiang Li,Dexun Zou,Yanping Liu
Due to the persistence and toxicity of PAHs, the accumulation of PAHs in soil causes environmental challenges. Utilizing nanoparticles to activate persulfate (PS) is an eco-friendly and cost-effective method for degrading PAHs. Herein, an advanced oxidation system with Fe 3 O 4 and CeO 2 loaded on BC as PS activators (Fe 3 O 4 -Ce@BC/PS) has been constructed, achieving a total removal of 89.34 % of PAHs from soil at 48 h of reaction at room temperature. Notably, High Resolution Transmission Electron Microscope analysis confirmed the presence of a CeO 2 -Fe 3 O 4 heterojunction, and Density functional theory calculations further revealed the key function of this structure. It reduced the adsorption energy of PS (−4.03 eV), thereby improving its utilization efficiency. In addition, during the reaction process, OH and SO 4 − as the main active species collaborated with 1 O 2 , O 2 − and electron transfer to degrade PAHs. In a word, the Fe 3 O 4 -Ce@BC/PS system developed in this study provided an effective solution to the problem of PAHs-contaminated soil.
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
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Xun Liu,Yufei Shu,Yu Pan,Guoshen Zeng,Meng Zhang,Chaoqun Zhu,Youmei Xu,Aling Wan,Mengxia Wang,Qi Han,Bei Liu,Zhongying Wang
The persistence and ecological impact of per- and poly-fluoroalkyl substances (PFAS) in water sources necessitate effective and energy-efficient treatment solutions. This study introduces a novel approach using cerium dioxide (CeO 2 ) electrodes enhanced with oxygen vacancy (O v ) to catalyze the defluorination of PFAS. By leveraging the unique affinity between cerium and fluorine-containing species, our approach enables adsorptive preconcentration and catalytic degradation at low oxidation potentials (1.37 V vs. SHE). Demonstrating high removal and defluorination efficiencies of perfluorooctanoic acid (PFOA) at 94.0% and 73.0%, respectively, our approach also proves effective in the environmental matrix. It minimizes the impacts of co-existing natural organic matter and chloride ions, crucial benefits of operating at lower oxidation potentials. The role of O v in CeO 2 is validated by both experimental results and density functional theory modeling, demonstrating that these sites can activate the C–F bond and substantially reduce the energy barriers for defluorination. Consequently, our CeO 2 -based method not only achieves defluorination efficiencies comparable to more energy-intensive techniques but does so while requiring less than 0.62 kWh/m 3 per order. This positions our approach as a promising, cost-effective alternative for the remediation of PFAS-contaminated waters, emphasizing its relevance and effectiveness in environmental remediation scenarios.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
AICHE JOURNAL
·
2024
·
IF 3.5
Yan Shao,Bohong Wu,Boya Qiu,Rongsheng Cai,Cui Quan,Ningbo Gao,Feng Zeng,Xiaolei Fan,Huanhao Chen
Synergistic Pd–In 2 O 3 catalysts are promising candidates for producing methanol via CO 2 hydrogenation, and the metal phases in them can be tuned by thermal reduction treatment affecting the catalytic activity significantly. This work presents a comprehensive investigation to gain an insight into the effect of thermal reduction temperature on the variation and interaction of Pd and In 2 O 3 phases supported on CeO 2 (viz., PdIn/CeO 2 ) and their correlations with CO 2 hydrogenation toward methanol synthesis. The findings show that Pd/In-rich PdIn alloys and In 2 O 3 with relatively strong interaction are key phases (by reducing the PdIn/CeO 2 at 300°C) for promoting methanol formation, leading to a high selectivity to methanol at 78.9% and space–time yield (STY) of 3.6 g CH3OH g PdIn −1 h −1 . A further increase in reduction temperature (from 300 to 500°C) promoted the formation of homogenized PdIn intermetallic alloys with significantly poor ability for H 2 dissociation and CO 2 activation, and hence poor methanol yield.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 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）