JOURNAL OF HAZARDOUS MATERIALS
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2017
·
IF 6.065
Shunxing Li,Jiabai Cai,Xueqing Wu,Biwen Liu,Qiaoying Chen,Yuehai Li,Fengying Zheng
An solar-light-driven and bifunctional photocatalyst was designed for photo-reduction of Cr(VI) and selective photo-oxidation of benzyl alcohol into benzaldehyde in the presence of water under ambient conditions. Double-shelled and sandwiched TiO 2 @Pt@CeO 2 hollow spheres were prepared by using functionalized polystyrene spheres, sol-gel, hydrothermal reaction, and calcination. The Pt nanoparticles (NPs) were controllably loaded between the TiO 2 shell and CeO 2 shell. Under solar-light irradiation, the photo-reduction rate of Cr(VI) (μmol h −1 ) was in the order of TiO 2 @Pt@CeO 2 (1.901) > TiO 2 @CeO 2 (1.424) > TiO 2 (1.040) > CeO 2 (0.992). Among the above-mentioned photocatalysts, the conversion rate of benzyl alcohol for TiO 2 @Pt@CeO 2 was also the best. These results were attributed to the combination of TiO 2 and CeO 2 as photocatalyst and oxygen buffer, the double-shelled and sandwiched nanostructure, and the addition of Pt NPs as cocatalyst and electron trap site, which could store and shuttle photo-generated electrons, reduce the recombination of the electron-hole, and then enhance photo-generation of active radicals. This conclusion was verified by the electron paramagnetic resonance (EPR) spectroscopy. Considering the versatile combination of photocatalyst, oxygen buffer and cocatalyst, this work could provide new insights into the design of high-performance bifunctional photocatalysts for heavy metal removal and selective synthesis.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 34
·21057-21065
·
IF 3.361
Dongren Cai,Bin Chen,Zhongliang Huang,Xiaoli Zeng,Jingran Xiao,Shu-Feng Zhou,Guowu Zhan
Herein, a series of metal oxide/CeO2 (M/CeO2) nanocomposites derived from Ce-benzene tricarboxylate (Ce-BTC) adsorbing with different metal acetylacetonate complexes were prepared for CO oxidation under four different CO gas atmospheres. It was demonstrated that Cu/CeO2 exhibited the highest catalytic activity and stability in CO oxidation. Remarkably, both O2 selectivity and CO selectivity to CO2 are 100% in most of the investigated conditions. Several analytical tools such as N2 adsorption–desorption and powder X-ray diffraction, were employed to characterize the prepared catalysts. In addition, the excellent catalytic performance of Cu/CeO2 in CO oxidation was revealed by H2 temperature-program reduction experiment, X-ray photoelectron spectroscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy. The result showed that high oxygen vacancy and high CO adsorption capacity (Cu+–CO) caused by the electron exchanges of Cu2+/Cu+ and Ce3+/Ce4+ pairs (Ce4+ + Cu+ ⇆ Ce3+ + Cu2+) are two key factors contributing to the high oxidation performance of Cu/CeO2 catalyst.
研究领域:
催化化学
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材料科学
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2021
·
IF 4.539
Yu Lei,Yixing Hao,Hao Cheng,Jianfeng Ma,Yong Qin,Yong Kong,Sridhar Komarneni
Fe 2 O 3 @CeO 2 nanocomposites were synthesized by water bath heating method to activate NaHSO 3 for Orange II dye (50 mg L −1 ) degradation, which reached up to 98.2% within 120 min. The Fe 2 O 3 @CeO 2 and NaHSO 3 dosages and the molar ratios of Ce and Fe in Fe 2 O 3 @CeO 2 were investigated to obtain the optimum conditions as follows: 0.02 g Fe 2 O@CeO 2 , 0.1 g NaHSO 3 and the molar ratio of Ce and Fe was 5:2 (designated as Ce-Fe-1, or simply Fe 2 O 3 @CeO 2 ). In addition, Fe 2 O 3 @CeO 2 catalyst displayed superior catalytic performance to those materials that were previously reported, as verified by the good stability (reached 90.9% after three cycles) and high degradation rate of Orange II (98.2%) of the currently developed material. Existence of · SO 4 – and · OH radicals were verified by Electron Spin Resonance Spectroscopy during degradation, and these radicals are proposed to have high degradation efficiency of Orange II. On the basis of the detected radicals, a possible degradation mechanism was proposed to provide more choices for the application of sulfite in advanced oxidation processes (AOPs).
研究领域:
环境科学
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材料科学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
·
IF 9.446
Qixing Zhou,Shuanglong Ma,Sihui Zhan
Ordered mesoporous Ag/CeO 2 nanocomposites were prepared by combining nanocasting with photo-assisted reduction. The heterogeneous photoreactivity of the prepared samples was tested for inactivating Escherichia coli ( E. coli ). These mesoporous Ag/CeO 2 nanocomposites exhibited superior photocatalytic disinfection efficiency than mesoporous CeO 2 and bulk CeO 2 , respectively. Doping Ag species could extend the absorption range to visible light area and enhance the concentration of Ce 3+ ions and oxygen vacancies, which had significant influence on the surface properties of CeO 2 . Moreover, it is the first time to verify that created midgap states through doping Ag can significantly lower the threshold of incident photon energy and broaden the adsorption spectrum demonstrated by experimental studies and density functional theory (DFT) calculations. The enhanced disinfection mechanism was attributed to the fact that the novel mesoporous structure can promote the mass transfer process and the interfacial interaction between Ag species and CeO 2 and lead to reduced recombination of free charges, rapid separation and transportation of photogenerated electrons-holes. This work provides a new method to develop novel mesoporous plasmonic photocatlysts for disinfection using solar radiation.
研究领域:
环境科学
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微生物学
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材料科学
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DOI
高影响因子
Materials Today Communications
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2024
·
IF 3.7
Ke Yang,Sisi Cheng,Ziqin Yao,Shijia Li,Yuting Yang
Recently, the remarkable properties of ternary transition metal oxides with spinel structure derived from metal-organic frameworks (MOFs) have attracted researchers’ attention in the field of electrochemistry . In this work, zeolitic imidazolate frameworks (Zn-ZIF-67) was grown in situ on the surface of another metal organic framework (Ce-BTC) by internal expansion growth method (IEGM), and then the bow shaped ZnCo 2 O 4 /CeO 2 nanocomposite was prepared by using the resulting complex as template. When applied as enzyme-free glucose sensor, the bow shaped ZnCo 2 O 4 /CeO 2 nanocomposite shows good catalytic performance of glucose oxidation , especially the sensitivity value(2161.78μA·mM -1 ·cm -2 ) is higher than most of the reported results, with a very short response time (<1 s), and a low detection limit of 0.055 μM (S/N = 3). Furthermore, the modified electrode can continue to function correctly even when exposed to a range of interference-causing compounds and can be used for extended periods of time in air. Utilizing fruit juice to test this enzyme-free glucose sensor yielded good results, raising the possibility of future applications.
研究领域:
材料科学
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生物医学工程
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分析化学
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DOI
高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 14
·1672-1680
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IF 2.896
Yalin Wu,Liping Lu,Zhihui Yu,Xiayan Wang
Based on the strategy of increasing the number of oxygen vacancies to improve the catalytic performance, we have developed a novel electrochemical sensor based on the multivalent metal oxides cerium dioxide and manganous oxide (Mn3O4/CeO2) for reliable determination of extracellular hydrogen peroxide (H2O2) released from living cells. The Mn3O4/CeO2 nanocomposite was characterized by high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electrochemical performance of the Mn3O4/CeO2 nanocomposite modified glassy carbon electrode (Mn3O4/CeO2/GCE) was investigated. Owing to the abundant oxygen vacancies and strong synergistic effect between the multivalent Ce and Mn, the sensor exhibited excellent catalytic activity and selectivity for the electrochemical detection of H2O2 with a low quantitation limit of 2 nM. Moreover, Mn3O4/CeO2/GCE exhibited excellent reproducibility, repeatability, and long-term storage stability. Because of these remarkable analytical advantages, the constructed sensor was able to determine H2O2 released from living cells with satisfactory results. The results showed that the Mn3O4/CeO2 sensor is a promising candidate for a nanoenzymatic H2O2 sensor with the possibility of applications in physiology and diagnosis.
研究领域:
生物医学工程
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分析化学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 53
·47966-47973
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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
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催化化学
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产品关联
DOI
高影响因子
ACS Sensors
·
2025
·
IF 9.1
Weirong Zhou,Guoxuan Gu,Yuan Gao,Jiayin Han,Ning Yu,Chao Liao,Geyu Lu
Monitoring trace levels of nitrogen oxides (NOx) in high-humidity agricultural greenhouse environments is essential for both crop growth and workers’ health. However, achieving reliable NOx detection under extreme humidity remains challenging. Herein, this work presents an ultralow-detection-limit and highly humidity-tolerant NOx sensor based on Ag2Te/CeO2 nanocomposites. To the best of our knowledge, this is the first demonstration of Ag2Te/CeO2 heterostructures for gas sensing. Among the as-prepared samples, the optimal Ag2Te/CeO2 sample, with a molar ratio of 1:2, exhibited superior response and an ultralow detection limit of 5 ppb NO2 at 65 °C. The sensor response retained over 92% of its regular response even at 99% relative humidity. Density functional theory (DFT) calculations suggest that minimal H2O adsorption on Ag2Te and strong NO2 adsorption on CeO2, along with the formation of an n–n heterojunction, synergistically enhanced performance. Moreover, the sensor was further integrated into an Internet of Plants (IoP) environmental monitoring system. This work provides a new strategy for designing humidity-tolerant NOx sensors and offers a core device for smart agriculture.
研究领域:
材料科学
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环境科学
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农业技术
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Guowei Wang,Xue Ma,Jue Liu,Lifan Qin,Bing Li,Yuanan Hu,Hefa Cheng
A novel direct Z-scheme NiGa 2 O 4 /CeO 2 nanocomposite was designed and prepared via simple sol-hydrothermal and calcination methods, and its sonocatalytic activity was tested by studying the degradation of a model antimicrobial agent, malachite green (MG), under ultrasonic irradiation. Near complete (96.2%) degradation of MG (at 10 mg/L) could be achieved by the NiGa 2 O 4 /CeO 2 nanocomposite (at 1.0 g/L) after ultrasonic irradiation (40 kHz, 300 W) for 60 min at 25 °C. Under the same conditions, only 51.2 and 72.0% of the MG degraded in the presence of NiGa 2 O 4 and CeO 2 (at 1.0 g/L), respectively. These results demonstrate that the direct Z-scheme NiGa 2 O 4 /CeO 2 nanocomposite has excellent sonocatalytic activity, which is attributed to the matching band-gaps between NiGa 2 O 4 and CeO 2 . The sonocatalytic activity of NiGa 2 O 4 /CeO 2 nanocomposite decreased by 17% after four cycles of reuse, which is indicative of relatively good reusability. Scavenging experiments revealed that sonocatalytic degradation of MG results from the combined action of hydroxyl radicals ( OH) and holes (h + ), with the latter having a greater contribution. The pathways and mechanism of MG degradation were proposed based on the degradation intermediates detected. The results demonstrate that the prepared direct Z-scheme NiGa 2 O 4 /CeO 2 nanocomposite worked as designed and exhibited high and stable sonocatalytic activity during MG degradation, and could thus serve as a promising candidate in sonocatalytic treatment of other organic pollutants in wastewaters. The findings also provide new insights on the mechanism of sonocatalytic degradation and the design of efficient Z-scheme sonocatalysts.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 9
·1733-1738
·
IF 3.741
Wang Nan,Sun Jianchao,Chen Lijian,Fan Hai,Ai Shiyun
A nanomaterial of the chemical composition Cu 2 (OH) 3 Cl-CeO 2 and with a large surface area is shown to be a viable peroxidase mimetic. It was synthesized by co-precipitation of an aqueous solution containing Ce(III) chloride, Cu(II) chloride and hexamethylenetetramine by adding an ionic liquid. The material was characterized by scanning electron microscopy and X-ray powder diffractometry. The composite possesses peroxidase-like activity and catalyzes the oxidation of the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine by H 2 O 2 to produce a blue product. Based on this finding, a simple, rapid and selective colorimetric method was worked out for the determination of glucose and cholesterol by using the respective oxidases and by quantifying the H 2 O 2 formed. Both glucose and cholesterol can be determined by this method at levels as low as 50 µM.
We found that the newly synthesized Cu 2 (OH) 3 Cl-CeO 2 composite material possesses intrinsic peroxidase-like activity, and this finding was applied to design a rapid and selective colorimetric assay for H 2 O 2 , glucose and cholesterol.
研究领域:
生物化学
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医学检测
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纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemNanoMat
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2017
·Vol. 4
·期 2
·213-219
·
IF 2.937
Xuan Cai,Libo Shi,Hongli Zhao,Minbo Lan
Graphical It's super ! The p-n junction was introduced to electrochemical catalysts for superoxide detection. Based on the superoxide dismutase mimic activity of CeO 2 and the high electrochemical catalytic activity of CuO, a non-enzymatic superoxide sensor was established. Owing to the construction of a p-n heterojunction, the sensing performances of p-CuO/n-CeO 2 composites were further enhanced. This method could serve as an effective strategy to overcome the intrinsic defects of semiconductor catalysts and improve their applications in electrochemical sensors. The performance of electrochemical sensors is mainly limited by the intrinsic properties of electrocatalysts fabricated on the electrode. Introducing a p-n heterojunction into semiconducing electrocatalysts is an effective strategy to enhance the sensing performance. In this paper, p-n-heterojunction-based CuO/CeO 2 nanocomposites were synthesized by a simple hydrothermal process, and the effect of different Cu/Ce molar ratios was explored. p-CuO/n-CeO 2 was found to exhibit higher conductivity and electrocatalytic activity toward the target superoxide anion (O 2 .− ) when compared to both bare CuO and CeO 2 . Characterization shows that different Cu/Ce ratios in p-CuO/n-CeO 2 materials result in a considerable variation in the Ce 3+ /Ce 4+ level, and energy band gap of CeO 2 , greatly affecting the electrochemical performance of p-CuO/n-CeO 2 . Under optimized conditions, these sensors exhibit high sensitivity and low detection limit toward O 2 .− . These results demonstrate that the performance of semiconductor-based electrochemical sensors may be enhanced by the electron-transfer process of p-n junction interfaces.
研究领域:
分析化学
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生物医学工程
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Hongwang Liu,Yining Zhang,Sibao Liu,Sha Li,Guozhu Liu
Ammonia is a promising hydrogen storage material due to its ease of storage and decomposition to CO x -free hydrogen. Herein, we report colloidal solution combustion synthesis (CSCS) to construct Ni-CeO 2 nanocomposite catalysts for efficient ammonia decomposition to generate hydrogen. Unlike conventional supported Ni/CeO 2 catalyst, the prepared Ni-CeO 2 nanocomposite catalyst exhibited nickel embedded in CeO 2 matrix with enhanced metal-support interaction. The physicochemical properties and metal-support interaction of the catalysts can be tuned by adjusting the amount of silica sol template. The resulted Ni-CeO 2 nanocomposite catalysts exhibited outstanding catalytic performance in terms of activity and stability. The hydrogen production rate reached 32.9 mmol g cat −1 min −1 at 500 °C, which is superior to other state-of-the-art Ni-based catalysts and even comparable or better than some reported Ru-based catalysts. The systematic characterizations demonstrated that the unique Ni-CeO 2 nanocomposite structure with enhanced metal-support interaction, not only provided a rich Ni-CeO 2 interface to stabilize small-sized Ni nanoparticles, but also had a high concentration of oxygen vacancy to strengthen electronic metal-support interaction, making nickel surface electron-rich. The integrated studies of kinetics, temperature-programmed surface reaction, and DFT calculations corroborated that this enhanced metal-support interaction including geometric and electronic effects, favored the enrichment of NH 3 on the catalyst surface and facilitated rate-determining N≡N bond formation step, thereby boosting the reaction rate. This study highlights the importance of designing new structural catalysts with enhanced metal-support interaction for boosting hydrogen production from ammonia decomposition.
研究领域:
催化
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材料科学
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化学工程
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物理化学
✓ 已验证
产品关联
DOI
高影响因子