JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2018
·Vol. 88
·期 3
·654-659
·
IF 1.745
Wang Lijuan,Lv Hua,Li Binjie,Zhao Yanbao,Sun Lei
Flower-like ceria (CeO 2 ) architectures consisting of well aligned nanosheets were first synthesized by a glycol solvothermal method. The size of CeO 2 architectures is about 5 μm in width and 10 μm in length, with the nanosheets thickness below 100 nm. Subsequently, the adsorbed Ag ions on the surface of CeO 2 were in situ reduced to form Ag nanoparticles (NPs), leading to the fabrication of Ag/CeO 2 hybrid architectures (HAs). The formed Ag NPs with sizes of 20–40 nm were uniformly loaded on the surface of the CeO 2 sheets. The antibacterial properties of Ag/CeO 2 HAs against Gram-negative E. coli and Gram-positive S. aureus were evaluated by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and a filter paper inhibition zone method. The results demonstrated that Ag/CeO 2 HAs displayed excellent antibacterial activity toward S. aureus and E. coli , which were attributed to the synergistic antibacterial effect between Ag NPs and CeO 2 in HAs . Here, CeO 2 nanoflowers as a new substrate could restrict Ag NPs aggregations and improve their antibacterial activities. Therefore, the resulted Ag/CeO 2 HAs would be considered as a promising antibacterial agent.
研究领域:
材料科学
·
微生物学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Richuan Rao,Hanwen Liang,Chunming Hu,Huaze Dong,Xiongzi Dong,Yongqiang Tang,Song Fang,Qiang Ling
Ag-CeO 2 nanoassemblys are prepared with a simple melamine-induced thermal decomposition method. Ag-CeO 2 nanoassemblys have a structure composed of Ag nanoparticles and CeO 2 nanoparticles. For Ag-CeO 2 nanoassemblys, Ag introduction can partially or completely activate lattice oxygen species of CeO 2 nanoparticles and however, the ease of Ag-CeO 2 interface oxygen activation is strongly influenced by their pyrolysis temperature. Ag-CeO 2 nanoassemblys prepared at 350 °C have only partial activation of CeO 2 surface oxygen. If the calcination temperature increases to 400 °C, Ag-CeO 2 nanoassemblys are fully activated to form more reducible interfacial lattice oxygen and to promote their low-temperature reductivity. Although excessive calcination temperature (500 °C) induces full activation of Ag-CeO 2 interface lattice oxygen, Ag-CeO 2 nanoassemblys will construct a new Ag-CeO 2 interface that is relative difficult to reduce, causing a less amount of reducible interface lattice oxygen provided at higher temperature. Ag-CeO 2 nanoassemblys are investigated to reveal the relationship of Ag-CeO 2 interfacial oxygen activation and CO catalytic oxidation performance. Ag-CeO 2 nanoassemblys with more interfacial lattice oxygen provided at lower temperature are found to have higher catalytic activity than that catalyst with the partially or excessively activated interfacial oxygen.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 10
·2129-2139
·
IF 5.773
Houlin Wang,Shuang Liu,Zhen Zhao,Xin Zou,Minghan Liu,Wei Liu,Xiaodong Wu,Duan Weng
Different Ag/CeO2 catalysts with uniform structures and diverse surface oxygen vacancy (VO-s) contents were synthesized via a modified solution combustion method. Based on the results of Raman spectroscopy, H2-TPR and isothermal soot oxidation, it was suggested that even with gaseous O2 participating in the reaction, ceria surface sites around the catalyst–soot contact points can still be reduced by soot gradually. This interfacial reduction led to the generation of extra VO-s without changing the oxygen vacancies in the bulk of CeO2. Notably, this VO-s dynamic change and the insufficient O2− regeneration/delivery further resulted in the activation and deactivation of Ag/CeO2 during reaction with soot. This means that both the existence of ceria VO-s and its dynamic change during reaction may have a crucial influence on catalyst behavior. By further exploring these activity variations, the VO-s content, catalyst–soot contact condition and extra oxygen supplier were proved to be the three most important structural factors behind the soot oxidation activity of all the ceria-based catalysts. In this sense, Ag/CeO2 catalysts with appropriate morphology and moderate initial VO-s content may exhibit good activity for soot oxidation.
研究领域:
催化化学
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环境科学
·
材料科学
·
表面化学
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能源化学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2022
·
IF 5.304
Huan Jiang,Baihui Wang,Ruyi Tang,Yaoyu Tan,Mengyao Qi,Xia Zhang
Although thiourea and its derivatives are applied in medical, food, and chemical industries, sensitive thiourea detection remains a challenging and noticeable topic. Surface-enhanced Raman spectroscopy assay based on an enzyme-inhibition strategy is promising for the detection of thiourea residues. Therefore, in this study, Ag/CeO 2 nanomaterials with dual enzyme-Like Activities were synthesized to detection thiourea. We discovered that the Ag/CeO 2 nanozymes demonstrated strong peroxidase-like activity and oxidase-like activity, moreover they can accelerate and catalyze 3,3′,5,5′-tetramethylbenzidine enzymatic reaction , with significantly increasing the Raman signal. Instead, once thiourea was introduced into Ag/CeO 2 nanozymes, due to the influence of thiourea molecules occupation and nanozymes aggregation, the peroxidase-like activity and oxidase-like activity of Ag/CeO 2 decreased sharply, and the colorless substrate 3,3′,5,5′-tetramethylbenzidine would not undergo color changes. Based on this observation, a Raman method for detecting thiourea using oxidized 3,3′,5,5′-tetramethylbenzidine as a probe molecule was developed. The Raman intensity showed a good linearity for the concentration of thiourea in the range of 10 −11 M−10 −1 M with a correlation coefficient of R 2 = 0.9881, and the limit of detection is 2.4 × 10 −13 M. Therefore, the proposed Raman mode sensors exhibited excellent selectivity and anti-interference ability which offers a new avenue for exploiting environmental monitoring.
研究领域:
分析化学
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环境科学
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生物医学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Zhichao Shang,Zhongxiang Yang,Yang Xiao,Xiaohong Wang
The various ordered mesoporous Ag/CeO 2 catalysts were successfully prepared using a facile silica-templated solution combustion synthesis method (TSCS). Utilizing X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET), photoluminescence (PL) and UV–vis diffuse reflectance spectrometry (DRS), etc., the morphological, structural, crystalline, surface and optical properties of Ag/CeO 2 were investigated. It was found that the removal of the template (SiO 2 ) resulted in the formation of ultrafine mesoporous Ag/CeO 2 composites, and the specific surface area increased to 98.6 m 2 /g. The 15 % Ag/CeO 2 composite showed the best photocatalytic performance (97 % at 120 min), which was approximately 10 times higher as compared to the conventional SCS (Solution Combustion Synthesized) CeO 2 . In addition, a mechanism of the photocatalytic degradation of Rhodamine B (RhB) was proposed, where the reactive species ·O 2 − and h + played important roles in the degradation of pollutants.
研究领域:
材料科学
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环境科学
·
催化
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2022
·
IF 12.92
Anxiang Guan,Yueli Quan,Yangshen Chen,Zhengzheng Liu,Junbo Zhang,Miao Kan,Quan Zhang,Haoliang Huang,Linping Qian,Linjuan Zhang,Gengfeng Zheng
The electrocarboxylation reaction is an attractive means to convert CO 2 into valuable chemicals under ambient conditions, while it still suffers from low efficiency due to the high stability of CO 2 . In this work, we report a double activation strategy for simultaneously activating CO 2 and acetophenone by silver-doped CeO 2 (Ag-CeO 2 ) nanowires, featuring as an effective electrocatalyst for electrocarboxylation of acetophenone with CO 2 . Compared to the Ag foil, Ag nanoparticles and CeO 2 nanowires, the Ag-CeO 2 nanowire catalyst allowed to reduce the onset potential difference between CO 2 and acetophenone activation, thus enabling efficient electrocarboxylation to form 2-phenyllactic acid. The Faradaic efficiency for producing 2-phenyllactic acid reached 91% at −1.8 V versus Ag/AgI. This double activation strategy of activating both CO 2 and organic substrate molecules can benefit the catalyst design to improve activities and selectivities in upgrading CO 2 fixation for higher-value electrocarboxylation.
研究领域:
化学
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环境科学
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材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Jiahui Gu,Hong Liu,Tingyu Peng,Shun Li,Li Xu,Jianming Zhang,Long Zhang
Plasmonic nanohybrids composed of semiconductors and plasmonic metal nanoparticles (NPs) have been intensively investigated in heterogeneous photocatalysis. The surface plasmonic resonance (SPR) effect of metal NPs plays a critical role in increasing light absorption and excitation of energetic carriers for photocatalysis. Most efforts are devoted to increasing the intrinsic absorptivity of the photocatalyst; however, the possible SPR scattering contribution of the metal NPs to photocatalysis has been long overlooked. In this work, we demonstrate a proof of concept of plasmonic scattering-enhanced absorption for efficient photocatalytic organic conversion in the visible to near-infrared wavelength region. With a multistep wet-chemical deposition approach, Ag NPs are encapsulated into the CeO2–Au system as the scattering core to form a Ag@CeO2–Au core@shell-satellite structure with a metal content of ∼30.6%. By varying the size (30–100 nm in diameter) and aggregation status (single NP or coupled NPs) of the Ag NP core, its scattering effect can be adjusted over a wide spectral range. This smart design results in scattered photon energy by the core composed of coupled 100 nm Ag NPs to greatly resonate with the SPR excitation of Au nanorods on the CeO2 surface over a wide spectral range from 400 to 900 nm, resulting in the confinement of the incident light in the optical path. The SPR scattering effect-induced light harvest and the near-field enhancement at the Au–CeO2 interface greatly boost the generation and separation of hot charge carriers for surface reaction, leading to a superior conversion efficiency of >90% in 3 h with a high selectively of ∼100% for oxidizing aminobenzyl alcohol to aminobenzaldehyde. This work reveals the immediate role of plasmonic scattering for light harvesting in photocatalysts.
研究领域:
化学
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材料科学
·
光催化技术
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 53
·47966-47973
·
IF 3.289
Yao Shi,Xiaoliang Zhang,Yongmei Zhu,Hongliang Tan,Xiangshu Chen,Zhang-Hui Lu
Ag–CeO2 nanocomposites (Ag@CeO2 NCs) with a core–shell structure have been successfully synthesized through the combination of a redox reaction and the reverse micelle technique without any additional reductants or surfactants. Under a N2 atmosphere, the redox reaction automatically occurs between Ag+ and Ce3+ in an alkaline solution, resulting in the formation of Ag@CeO2 NCs by the self-assembly process. By using the XRD, FE-SEM, TEM, XPS, and ICP methods, the characterized results of Ag@CeO2 NCs show that Ag nanoparticles (NPs) with a diameter of 3–7 nm are surrounded by CeO2 NPs. Compared to CeO2 supported Ag NPs, free Ag NPs, and CeO2, the as-synthesized Ag@CeO2 NCs exhibit a superior catalytic activity and high sustainability for the hydrogenation of 4-nitrophenol (C6H5NO3, 4-NP) and 2-nitroaniline (C6H6N2O2, 2-NA) with sodium borohydride (NaBH4) in water solution at room temperature. The Ag@CeO2 NCs can achieve a complete reduction of 4-NP and 2-NA with turnover frequencies (TOF) of 138.7 and 109.8 h−1, respectively. The durability tests show that the Ag@CeO2 NCs are still highly active for the reduction of 4-NP and 2-NA, preserving 98% and 95% of their initial catalytic activity even after ten runs.
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
JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Houlin Wang,Shuting Luo,Meisheng Zhang,Wei Liu,Xiaodong Wu,Shuang Liu
Though the catalytic oxidation of CO, NO and soot over CeO 2 could be understood within a similar Mars-van Krevelen-type mechanism, these reactions were likely to be driven by different active phases. In this work, several CeO 2 and Ag/CeO 2 nanorods with different contents of surface oxygen vacancies (V O-s ) and active oxygen species (O x − ) were designed as model catalysts. Their catalytic performance indicated that, CO oxidation was determined by pre-existing ceria V O-s , while O x − participated in NO and soot oxidation directly. Besides, by loading silver onto the high-temperature aged CeO 2 nanorods, Ag/CeO 2 catalysts with high availability of ceria lattice oxygen were obtained, whose low-temperature oxidation activity was proven comparable to that of the platinum catalysts. In this sense, the model designing in this work not only provided methods to find out proper reactivity descriptors, but also conferred low-cost catalysts with high practical potential.
研究领域:
催化
·
材料科学
·
化学工程
·
环境化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Meisheng Zhang,Baofang Jin,Yan Liu,Wei Liu,Duan Weng,Xiaodong Wu,Shuang Liu
In this work, O 3 activation was performed at 200 °C over two types of Ag/CeO 2 catalysts with nanocube- and nanorod-like morphologies, respectively. The O 3 -indcued surface O x − species (“O x − injection”) accelerated soot combustion over both catalysts temporarily. In contrast, the depletion of CeO 2 surface oxygen vacancies (Ce 3+ -V O-s ) caused by ozonization conferred to long-term activation. Specifically, the ozonized nanocubic Ag/CeO 2 with low initial Ce 3+ content not only benefited more from the “O x − injection”, but also exhibited good redox stability and high practical potential. Therefore, the combination of this catalyst with O 3 activation may result in efficient soot elimination in the particulate filters of vehicles.
研究领域:
催化
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
RARE METALS
·
2025
·
IF 11
Wang Ding,Qin Rui-Jie,Yu Jie-Jie,Hu Jin-Wu,Zhang Wen-Hui,Xu Hui,Xu Jing-Cheng,Liao Qiao-Bo,Li Hui-Jun,Wang Xu-Hui
The semiconductor gas sensors used for xylene gas detection in real time has been restricted by the inadequate sensitivity and selectivity. Constructing a bilayer cascade sensor with the catalysis-gas sensitivity synergistic is considered as an effective solution. Herein, the Ag@CeO 2 nanosheets are synthesized by heat treating the Ag@Ce-MOF, which synthesized via solvothermal method. The morphological evolution of cerium metal–organic framework (Ce-MOF), regulated by Ag ions, is investigated, and the transformation mechanism is proposed. The bilayer sensors were constructed by using WO 3 nanofibers, prepared via the electrospinning method, as the sensitive layer and the Ag@CeO 2 nanosheets as the catalytic layer, respectively. The bilayer sensors exhibit remarkable performance in response to xylene. The response value ( R a / R g ) of WO 3 /Ag@CeO 2 sensor to 10 ppm xylene gas reaches 32.13 at the operating temperature of 160 °C. Additionally, the sensor displays an exceptional response to even trace amounts of xylene, as low as parts per billion (ppb). The catalysis-gas sensitivity synergistic mechanism was elucidated by capturing catalytic intermediates using online mass spectrometry. These findings provide a novel strategy for benzene series (BTEX) sensor and offer a novel approach to prepare two-dimensional Ce-MOF and its derived materials with tailored properties. Graphical abstract
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2023
·Vol. 148
·期 21
·12311-12320
·
IF 4.4
Fang Jia,Yi Chengcheng,Pu Ping,Chen Chen,Yang Yi,Wang Jiaxin,Lin Bin
Ag/CeO 2 catalyst is synthesized by hydrothermal method, which has been studied under the effects of different catalyst content, ash and Ag load through activity and characterization tests. Ag loading increases the catalytic activity of CeO 2 , and the peak combustion temperature of soot decreases by 74 °C. The catalytic effect of Ag/CeO 2 is affected by catalyst content, Ag load and ash content. The optimum mass ratio of soot/catalyst is 1/10, and 10 mass% is the saturation value of Ag loading at CeO 2 . Ash inhibits the promoting effect of Ag/CeO 2 in the oxidation process of soot. This study provides a theoretical basis for the industrial application of Ag/CeO 2 catalyst in gasoline engine and also provides a research idea for the low-temperature oxidation of soot.
研究领域:
催化
·
环境科学
·
材料科学
✓ 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）