MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 2
·1-9
·
IF 6.232
Li Chi,Zhang Yuanyuan,Li Chunya,Wan Qijin,Ke Qiang,Yang Nianjun
Four CeO 2 nanomaterials with the morphologies of a nanoplate (CeO 2 -p), a nanocube (CeO 2 -c), a porous triangular microplate (CeO 2 -t), and of a porous hierarchical rod-stacked nanobundle (CeO 2 -b) were synthesized using a hydrothermal method. They were characterized by scanning and transmission electron microscopies, X-ray diffraction and X-ray photoelectron spectroscopy. Electrochemical characterizations reveal the tuning of their morphology and the presence of exposed crystal planes of CeO 2 that can be realized by changing the alkali sources. Among these materials, the CeO 2 -b features the largest specific surface and lowest electron transfer resistance towards the redox probe Fe(CN) 6 3-/4- . The best voltammetric response to dopamine and epinephrine is thus achieved by using the Nafion-CeO 2 -b coated electrode. A sensitive and selective method was developed that can voltammetrically detect dopamine (with a peak near 0.13 V vs. SCE), and epinephrine (with a peak near 0.25 V vs. SCE). The detection limits are 2.9 and 0.67 nM, respectively.
Schematic representation of morphology tailoring of CeO 2 and electrochemical sensing of dopamine and epinephrine on these CeO 2 samples with different morphologies
研究领域:
分析化学
·
材料科学
·
生物医学工程
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 47
·37585-37591
·
IF 3.84
Yunshi Liu,Hsueh-Shih Chen,Jia Li,Ping Yang
One dimensional (1D) CeO2 nanostructures have been successfully fabricated via a single nozzle electrospinning method and subsequent two-step calcination route by adjusting heating rates. The formation process of CeO2 nanotubes (NTs) and nanobelts (NBs) was investigated by observing the morphology evolution of fibers during calcination. Control of the heat-treatment procedure including solvent evaporation, the Kirkendall effect, polymer softening, and thermal decomposition of poly(vinylpyrrolidone) plays an important role in the morphologies of the samples. Well-dispersed and small Au nanoparticles (NPs) were deposited on 1D CeO2 nanostructures through a direct wet-chemical reaction or adding Au precursors during electrospinning. The results of the catalytic performance for CO oxidation suggest that CeO2 NTs display enhanced catalytic activities compared with CeO2 NBs. The loading of Au NPs significantly enhanced the catalytic properties of 1D CeO2 nanostructures. Because of the large surface areas, good crystallinity and the strong interfacial interactions between Au NPs and the CeO2 matrix, the 1% Au/CeO2 NTs exhibit superior catalytic activity with onset CO conversion at 65 °C and complete CO conversion at 142 °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
RSC Advances
·
2015
·Vol. 5
·期 72
·58237-58245
·
IF 3.84
Yuanmei Xu,Yiwei Zhang,Yuming Zhou,Sanming Xiang,Qianli Wang,Chao Zhang,Xiaoli Sheng
Uniform ceria hollow nanospheres composed of ceria nanocrystals have been synthesized via a simple one-step hydrothermal method without using any template. Afterwards, these hollow materials were used as support to prepare the Au/CeO2 catalyst for the reduction of 4-nitrophenol (4-NP). It was found that the obtained porous CeO2 hollow nanospheres were morphologically uniform, with an average diameter of 210 nm and high specific surface area of 167 m2 g−1. According to the basis of a time-dependent experiment, a self-assembly process coupled with an Ostwald ripening mechanism was proposed to explain the evolution of CeO2 hollow nanospheres. In comparison with the commercial CeO2 powder supported sample, the synthesized hollow Au/CeO2 nanospheres catalyst exhibited significantly enhanced catalytic activity. In addition, the results of cyclic stability of the catalyst indicated that similar catalytic performance without visible reduction could be found after 7 repeated cycles. As for this catalyst system, the unique porosity structures of the support, uniform distribution of metallic particles together with the high thermal stability of Au NPs were all responsible for the improved reaction properties.
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 THERMAL SPRAY TECHNOLOGY
·
2022
·Vol. 31
·期 8
·2463-2475
·
IF 2.839
Liu Ji,Chen Tongzhou,Duan Haitao,Yuan Chengqing,Bai Xiuqin
Cavitation erosion is a major failure mode of hydraulic turbine components. Coatings could be an effective solution to this problem. In this study, a CeO2-modified (1 wt%) dual-scale WC-10Co-4Cr powder (WC composed of 70 wt% micrometer WC (2.5 μm) and 30 wt% nanometer WC (100 ~ 200 nm)) was fabricated by agglomeration and sintering. CeO2-modified dual-scale WC-10Co-4Cr coatings (C-coating), dual-scale WC-10Co-4Cr coatings (D-coating), and micrometer WC-10Co-4Cr coatings (M-coating) were then deposited using a high-velocity oxygen fuel (HVOF). The mechanical properties and cavitation erosion behavior of these coatings were studied. The results showed that the CeO2-modified WC-10Co-4Cr coatings could effectively reduce decarburization in the powder preparation and HVOF process, the coatings having the highest WC retention rate. The C-coatings possessed a higher fracture strength (6.3 MPa m 1/2 ) and hardness (1348.2 HV0.3) than the D-coatings by more than 8.6 and 3.0%, respectively. The cavitation erosion resistance of the WC-10Co-4Cr coatings was affected by their microstructure and mechanical properties. The CeO2-modified coatings exhibited improved fracture toughness and hardness, reduced porosity, and, as a result, the C-coatings had the best cavitation erosion resistance.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2022
·
IF 7.968
Pijun Gong,De Fang,Feng He,Junlin Xie,Haitao Wu
Cake-like MnO 2 @CeO 2 catalyst with hierarchical nanosheets structure has been successfully constructed by in situ methods. The relationship between structure and activity of the MnO 2 @CeO 2 catalyst was characterized using various analytical techniques. It is identified that rich surface oxygen species and better reducibility were generated due to the strong synergistic effect between MnO 2 and CeO 2 , and hence nearly T 90 toluene conversion can be obtained for the 10%-MnO 2 @CeO 2 catalyst under 240–300 °C. In addition, it is found that after loading MnO 2 on the multi-layer CeO 2 support to form a hierarchical cake-like structure, the oxygen vacancies, Ce 3+ /Ce 4+ and BET surface area of MnO 2 @CeO 2 increased significantly, which is beneficial to toluene adsorption and reaction. Furthermore, the in situ DRIFTS study demonstrated that the lattice oxygen and surface oxygen both participate in the toluene oxidation , whereas surface active oxygens adsorbed on the oxygen vacancies will lead to deep oxidation by forming abundance intermediates.
研究领域:
催化化学
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环境科学
✓ 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
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
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2020
·Vol. 20
·期 9
·5539-5545
·
IF 1.134
Yin Hao Yong,Zheng Yi Fan,Wang Ling
A convenient and simple phenol electrochemical sensor was constructed based on the Au/CeO2/ g-C3N4 nanocomposites, which were obtained by loading the gold–cerium oxide (Au/CeO2) nanoparticle on graphite-like carbon nitride (g-C3N4)
through precipitation–reduction methods. The microstructure and morphology of Au/CeO2/g-C3N4 nanocomposite were verified using different techniques such as XRD, TEM, and HRTEM. Voltammetry and amperometry methods were used to study the electrochemical
performance of the constructed phenol electrochemical sensors. The results demonstrated evidently that the combination of Au/CeO2 and g-C3N4 may improve sensing performances of phenol determination. The detection linear range of the sensor was 10–90 μM
under the optimum parameters. The Au/CeO2/g-C3N4 based electrochemical sensor also has low detection limits (2.33 μM) and high sensitivities (0.1080 mA/μM) for phenol detection. In addition, the sensor also had considerably favorable anti-interference
performance. As a consequence, the sensor demonstrated that the electrochemical system provided a promising effective strategy for detection of phenol.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Yunzhu Wang,Yang Chen,Songshan Zhu,Di Song,Tianhao Ai,Sufang He,Yongming Luo
Steam reforming of glycerol (GSR) to produce hydrogen has been considered a sustainable and low-cost route for hydrogen production. The selection of a suitable catalyst support is crucial for achieving efficient hydrogen production at lower temperatures. CeO 2 has been widely used in heterogeneous catalysis and exhibits excellent low-temperature catalytic performance. However, different calcination mode may influence catalyst performance. In this study, the Ni/CeO 2 catalyst prepared by rapid calcination mode (Ni/CeO 2 -RC), was used for hydrogen production from GSR, and the Ni/CeO 2 catalyst with the conventional programmed-heating calcination method (Ni/CeO 2 -PC) was applied for comparison. The effect of different calcination modes on the physico-chemical properties of the catalysts was investigated through multiple characterizations such as N 2 adsorption-desorption, X-ray diffraction, hydrogen temperature programmed reduction, transmission electron microscopy, X-ray photoelectron spectroscopy, H 2 chemisorption, CO-oxygen storage capacity and conversion, temperature programmed oxidation, and Raman spectroscopy. The rapid calcination mode promoted stronger metal-support interactions in Ni/CeO 2 -RC, inducing the formation of nickel species highly susceptible to reduction due to the electronic effect. Additionally, rapid calcination facilitated the increased incorporation of nickel particles into the cerium dioxide lattice, leading to lattice distortions, thereby contributing to the formation of more oxygen vacancies. The abundant oxygen vacancies promoted the activation of water, thus realizing the high H 2 selectivity of Ni/CeO 2 -RC. Moreover, the strong oxygen storage-release ability of Ni/CeO 2 -RC facilitated the oxidative effect of carbon deposition and the strong Ni–CeO 2 interaction effectively inhibit sintering of nickel nanoparticles on Ni/CeO 2 -RC. Therefore, Ni/CeO 2 -RC exhibited outstanding catalytic stability, remaining active for 35 h without deactivation, whereas Ni/CeO 2 -PC rapidly deactivated after 25 h of reaction.
研究领域:
催化化学
·
能源材料科学
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产品关联
DOI
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Jinling Li,Hui-Ling Peng,Changchun Wen,Peijing Xu,Xing-Can Shen,Cunji Gao
The therapeutic effect of photothermal therapy (PTT) and photodynamic therapy (PDT) is severely limited because of the shallow tissue penetration depth of the first near-infrared (NIR-I) light. Multifunctional nanotheranostics irradiated by the second near-infrared (NIR-II) light have received wide interest with respect to deeper tissue penetration, and sonodynamic therapy (SDT) synergistic phototherapy can achieve the complete elimination of tumors. Herein, we successfully constructed a single NIR-II light-induced nanotheranostic using cerium oxide (CeO2–x) with abundant oxygen vacancies for photoacoustic imaging-guided SDT-enhanced phototherapy for the first time. CeO2–x with surface crystalline disorder showed extensive NIR-II region absorption and an outstanding photothermal conversion ability. In addition, the CeO2–x layer with numerous oxygen defects can promote the separation of holes and electrons by ultrasound irradiation, which can remarkably enhance the efficacy of phototherapy to achieve high-efficiency tumor ablation. CeO2–x was surface modified with hyaluronic acid (HA) to prepare CeO2–x@HA to allow active tumor targeting efficiency. Both cell and animal experiments confirmed that all-in-one CeO2–x@HA exhibited a high therapeutic efficacy of SDT-enhanced PDT/PTT under 1064 nm laser irradiation, which achieved complete tumor eradication without systemic toxicity. This study significantly broadened the application of NIR-II-responsive CeO2–x for photoacoustic imaging-mediated SDT-enhanced phototherapy to the highly efficient and precise elimination of tumors.
研究领域:
肿瘤学
·
生物医学工程
·
纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yu Pan,Xun Liu,Meng Zhang,Qi Han,Yufei Shu,Mengxia Wang,Bei Liu,Zhongying Wang
The presence of excess fluoride ions in drinking water has raised widespread concerns, necessitating the development of effective methods for its removal. Cerium dioxide (CeO 2 ) holds promise as a selective adsorbent for fluoride ions, due to its exceptional affinity for fluoride and stability across a wide pH range. However, the impact of intrinsic properties of CeO 2 on its adsorption characteristics and mechanisms remains unclear. In this study, we prepared a range of CeO 2 materials with diverse intrinsic properties by adjusting the annealing temperature and atmosphere. Through a series of characterization techniques, we discovered a correlation between the content of oxygen vacancies, Ce(III) species, and surface hydroxyl groups (–OH), all of which decreased simultaneously with increasing air annealing temperature. With respect to the adsorption performance, the highest fluoride adsorption capacity of 111.1 mg g −1 was observed in un-CeO 2 , representing the nanomaterials with the highest oxygen vacancies. This capacity gradually decreased to 29.1 mg g −1 in 800-CeO 2 . Following fluoride adsorption, the oxygen vacancy density, Ce(III) content, and surface –OH content of all CeO 2 materials decreased. When CeO 2 materials were annealed in H 2 for 1 h, the F − adsorption density increased due to the formation of more oxygen vacancies and surface –OH. Based on our findings, we conclude that oxygen vacancies play a critical role in determining whether fluoride ions can successfully exchange with surface –OH groups and enter the crystal lattice of CeO 2 , which significantly affects the adsorption performance. The pivotal role of oxygen vacancies, as proposed in this study, provides a valuable direction for future research aimed at enhancing the fluoride adsorption performance of CeO 2 .
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
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2016
·Vol. 94
·期 12
·2276-2281
·
IF 1.066
Dongjing Liu,Weiguo Zhou,Jiang Wu
The high-temperature H 2 S removal at 500–700 °C was conducted over CuO-CeO 2 /ZSM-5 composites prepared with sol-gel method. 7Cu3Ce/ZSM-5 partially reacting at 500 °C yielded Cu 7 S 4 and Cu 2 S. The major sulphidation products at 600 °C were Ce 2 O 2 S, Cu 2 S, CuS, and S. Sulphidation of 7Cu3Ce/ZSM-5 at 700 °C yielded Ce 2 S 3 , Cu 2 S, Cu 2 S, and S. Sulphidation of 7Cu3Ce/ZSM-5 with 20 % H 2 and 20 % CO generated the same products Ce 2 O 2 S, Cu 2 S, Cu 2 S, and S. Increase in the degree of crystallinity of 7Cu3Ce/ZSM-5 resulted in the decrease of sulphur capacity during the sulphidation and regeneration process. Experimental results showed that the activity of CuO improved by adding Ce; 7Cu3Ce/ZSM-5 performed the optimal sulphiation behaviour at 600 °C with sulphur capacity of 1429 μmol/g (micromoles of sulphur per gram) due to the synergy of CuO and CeO 2 . H 2 repressed sulphur removal, causing the reduction of sulphur capacity from 1429 to 1014 μmol/g. CO had little impact on sulphidation reaction; sulphur capacity only reduced from 1429 to 1221 μmol/g due to the presence of 20 % CO.
研究领域:
环境催化
·
能源化学工程
·
材料科学
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无机化学
·
气体净化技术
✓ 已验证
DOI
高影响因子
Water
·
2024
·Vol. 16
·期 5
·675
·
IF 3
Xiujuan Feng,Yanjun Zou,Sékou Mohamed Condé,Xiaoqing Wang,Chengliang Dong
Sulfate is a typical characteristic pollutant in mine water. Because of its high concentration and large discharge of mine water, it has become a difficult problem in mineral exploitation. Capacitive deionization (CDI) is an innovative and economical removal technology. There are few reports on the use of CDI to remove SO42−from mine water. In this study, a CeO2activated carbon electrode with good wettability, excellent electrochemical performance, and suitable pore structure was prepared by the sol-gel method. The application of the CeO2activated carbon electrode to the capacitive method for treating high SO42−mine water was investigated using simulated wastewater and actual mine water. The study structure shows that CeO2:activated carbon (AC) has the best wettability, the highest specific capacitance, and the lowest electrical conductivity when the mass ratio of CeO2is 5%. At 100 mg/L, the electrode has the maximum SO42−ion specific adsorption capacity (SAC). At 1 V and 20 mL/min, this value is measured. The electrode has a SAC value of 9.36 mg/g, far higher than the AC electrode’s 4.1 mg/g. The effect of CDI process factors such the voltage, flow rate, and initial concentration was studied to find the best treatment method. SAC retention is 91% after 10 adsorption–desorption cycles, demonstrating outstanding electrode performance. Under the best CDI process (1.4 volts, 30 mL/min), mine water was treated. After 20 cycles of treatment, the concentration of SO42−in mine water decreased from 1170 mg/L to 276.46 mg/L, and the removal rate was 76.37%. This study proved that the CeO2modified activated carbon electrode capacitance method can effectively remove sulfate ions and other ions from mine water.
研究领域:
环境科学
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材料科学
·
水处理工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）