Catalysts
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2018
·Vol. 8
·期 7
·257
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IF 3.465
Lin Li,Bo Jiang,Dawei Tang,Zhouwei Zheng,Cong Zhao
Chemical looping reforming (CLR) technique is a prospective option for hydrogen production. Improving oxygen mobility and sintering resistance are still the main challenges of the development of high-performance oxygen carriers (OCs) in the CLR process. This paper explores the performance of Ni/CeO2nanorod (NR) as an OC in CLR of ethanol. Various characterization methods such as N2adsorption-desorption, X-ray diffraction (XRD), Raman spectra, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), H2temperature-programmed reduction (TPR), and H2chemisorption were utilized to study the properties of fresh OCs. The characterization results show the Ni/CeO2-NR possesses high Ni dispersion, abundant oxygen vacancies, and strong metal-support interaction. The performance of prepared OCs was tested in a packed-bed reactor. H2selectivity of 80% was achieved by Ni/CeO2-NR in 10-cycle stability test. The small particle size and abundant oxygen vacancies contributed to the water gas shift reaction, improving the catalytic activity. The covered interfacial Ni atoms closely anchored on the underlying surface oxygen vacancies on the (111) facets of CeO2-NR, enhancing the anti-sintering capability. Moreover, the strong oxygen mobility of CeO2-NR also effectively eliminated surface coke on the Ni particle surface.Keywords:chemical looping reforming;hydrogen;oxygen carrier;CeO2;nanorod
研究领域:
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Jiahui Ma,Ning Xu,Yuxin Luo,Qi Liu,Yongping Pu
Ceria is widely used in industrial fields due to its unique chemical properties. In this work, a series of CeO 2 particles with controllable morphology, size, and defect concentration were obtained by a simple molten salt method. The adjustment of temperature and molten salt concentration has a considerable effect on the morphology and particle size of the final CeO 2 particles while prolonging the holding time has little effect. Ion doping and reducing atmosphere calcination were used to regulate the defect concentration to improve the chemical activity of CeO 2 particles. SEM results show that the morphology of CeO 2 particles transforms from sphere to octahedron under the two treatments. The Rietveld refinement results and the XPS spectra indicate that increasing calcination temperature, reducing atmosphere calcination and ion doping are beneficial to improving the oxygen vacancies and Ce 3+ concentration of CeO 2 samples, which are the reason for enhancing the photocatalytic activity of the samples. Moreover, the oriented attachment, agglomeration and merging of crystals formed by the decomposition of cerium precursors are the key to the growth of CeO 2 particles. Aggregates with exposed low-energy planes merge directly to form particles of various morphologies to maintain their own low energy.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS ES&T Engineering
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2025
·
IF 6.7
Ao Zhong,Kehan Li,Zeyu Duan,Haiqiang Wang,Zhongbiao Wu
Trimethylamine (TMA) is a common malodorous compound that poses serious environmental and health risks. Four different structures of cerium oxide (CeO2), namely, cubes, hollow spheres, octahedrons, and spindles, were successfully synthesized via a hydrothermal method and then used for TMA degradation in a vacuum ultraviolet photocatalytic oxidation system. All the synthesized catalysts exhibited enhanced activity compared with commercial CeO2. The hollow-sphere CeO2 demonstrated high catalytic performance, achieving 75.9% mineralization of TMA within 90 min and substantially reduced ozone generation (stable 0 ppm in outlet). Additionally, the total outlet concentration of secondary nitrogenous pollutants (NOx and NH3) remained below 2.5 ppm. In situ infrared spectroscopy was employed to elucidate the degradation pathway of TMA under vacuum ultraviolet irradiation, comparing sphere CeO2 with commercial CeO2. The superior TMA degradation performance of the hollow-sphere CeO2 was attributed to its higher Ce3+ ratio as well as increased oxygen, increased charge separation efficiency, and radical generation. This study provides new insights into the optimization of CeO2-based photocatalysts to efficiently degrade TMA and offers promising solutions for odor control and environmental protection.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Zhiqiang Wang,Xiaomei Zhou,Gehui Wang,Qing Tong,Haiqin Wan,Lin Dong
The elimination of toluene is an obligatory target with increasing VOC emission in recent years. This study successfully prepared a single-atom Ir catalyst (Ir1/CeO2) by a simple incipient wetness impregnation method, confirmed by in situ CO DRIFTS and AC-HAADF-STEM. Compared to the cluster Ir catalyst (Ir/CeO2-C), Ir1/CeO2 exhibited excellent catalytic performance, stability, and water resistance for the oxidation of toluene. By Raman, H2-TPR, O2-TPD, and XPS experiments, abundant oxygen defects and a unique Ir3+–Ov–Ce3+ structure were formed for the Ir1/CeO2 sample because it had a lower oxygen vacancy formation energy. Furthermore, the DFT results revealed that the Ir1/CeO2 sample had a lower ring-opening energy barrier and adsorption energy of the ring-opening products, which was the rate-determining step for the oxidation of toluene. This work provides instructive insights into the construction of Ir/CeO2 catalysts for the highly efficient removal of VOCs.
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Yakai Chen,Xinya Feng,Xiaohan Yu,Xingliang Xu,Jing Xu
Catalytic aldol condensation of biomass-derived furfural (FAL) with acetone (AC) into the single-condensation product 4-(2-furyl)-3-buten-2-one (FAC) is a potential and promising strategy for biomass improvement process and still challenging. Metal oxides exposed different crystal facets can regulate their surface structure and adsorption activation ability, which can provide an opportunity to enhance aldol condensation performance. Here, nanoparticles-CeO 2 (P-CeO 2 ), nanorods-CeO 2 (R-CeO 2 ) and nanocubes-CeO 2 (C-CeO 2 ) with (111), (110) and (100) plane predominant exposure was prepared to explore their catalytic performance for the aldol condensation of FAL with AC to obtain FAC. The serial detailed characterizations, experimental results and density functional theory calculation revealed that R-CeO 2 with a dominant (110) facet possesses appropriate surface adsorption energy, abundant oxygen vacancy (Ov) and excellent acid-base properties, which can effectively boost the adsorption and activation of FAL and AC and reduce the barrier of aldol condensation reaction based on the acid-base catalysis mechanism. The work would reveal the influence of CeO 2 crystal facet on the aldol condensation and provide a broad potential for the rational design of metal oxide catalysts for other acid-base catalytic reactions.
研究领域:
催化化学
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生物质能
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
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2023
·
IF 4.9
Songil Sin,Jiawei Ji,Lijun Cheng,Zhiwen Gu,Chong Tan,Kwangchol Ri,Changjin Tang
CeO 2 -based catalysts are widely investigated for selective catalytic reduction (SCR) of NO with NH 3 . Interaction of NO/O 2 with CeO 2 generally produces two surface species, i.e., nitrates and nitrites. However, the explicit quantification of these two species is still unresolved. Herein, we reported that spectrophotometry characterization was effective in determining surface adsorbed NO x species on CeO 2 by measuring the corresponding ions (NO 2 – and NO 3 – ) dissolved in aqueous solution. Experimental results show that both nitrate (–NO 3 ) and nitrite (–NO 2 ) species can be quantitatively evaluated and the accuracy is verified by calibrating with NO x -TPD result. Exclusive transfer of adsorbed NO x from catalyst surface to aqueous solution is confirmed and the dissolution process can be accelerated by ultrasonic treatment. Moreover, useful information related to evolution of surface NO x species under various conditions (O 2 treatment, different adsorption temperature and duration) and over different catalysts (Fe 2 O 3 , MnO 2 and MnO x –CeO 2 ) are provided. The result of present study demonstrates the potential of spectrophotometry for quantitative discrimination of surface NO x species on CeO 2 and other oxide-based materials, which is conducive to mechanism analysis of SCR reaction.
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
INORGANIC CHEMISTRY COMMUNICATIONS
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2023
·
IF 3.8
Xudong Liu,Fengyuan Liu,Junqi Li,Yuanpei Lan,Jian Yang,Arun Murali,Chaoyi Chen,Wei Zhang
To accurately evaluate the phase effects of MnO x in Mn-Ce catalysts towards to low temperature NO x removal performance with NH 3 , MnCO 3 @CeCO 3 OH was synthesized firstly and decomposed to MnO 2 @CeO 2 , Mn 2 O 3 @CeO 2 and Mn 3 O 4 @CeO 2 with similar size and morphology, this will avoid the influence of size and morphology on the experimental results. Experimental results show that the MnO 2 @CeO 2 exhibiting the best NO conversion ratio, which achieved nearly 96.5 % at a low temperature of 150 °C, and the catalytic performance order of MnO x @CeO 2 is determined as: MnO 2 @CeO 2 > Mn 2 O 3 @CeO 2 > Mn 3 O 4 @CeO 2 below 200 °C, and MnO 2 @CeO 2 > Mn 2 O 3 @CeO 2 ≈Mn 3 O 4 @CeO 2 at range of 200 –400 °C. But the N 2 selectivity of Mn 2 O 3 @CeO 2 reaches 96 % at 100 °C which was higher than that of MnO 2 @CeO 2 and Mn 3 O 4 @CeO 2 . Characterizations including BET, XRD, SEM, H 2 -TPR, NH 3 -TPD and FTIR show that MnO 2 @CeO 2 has maximum specific surface area, a stronger redox ability, and more surface acid sites.
研究领域:
催化材料
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
·
IF 8.1
Jihan Wu,Ying Chang,Shaohong Guo,Aiju Xu,Jingchun Jia,Meilin Jia
Ruthenium-based nanomaterials are considered to be promising electrocatalysts for HER due to their higher activity. However, the active site exposure is low, and the catalytic mass activity is low. In order to achieve the particular aims, several types of engineering, such as crystal engineering, topography engineering, heterostructures and support engineering, have been used to catalysts. Here we report RuO 2 supported on CeO 2 -NC, owing to the abundant heterostructures and the presence of oxygen vacancies, the RuO 2 /CeO 2 -NC catalyst showed outstanding HER performance (98.2 mV, 53 mV and 298 mV@100 mA cm −2 in acidic, alkaline and neutral, respectively). Moreover, RuO 2 /CeO 2 -NC also has an excellent electrocatalytic durability for 40 h. The experimental achievements show that oxygen vacancies and heterostructures could jointly enhance performance of catalyst HER.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
·
IF 9
Qinyu Zhou,Chong Tan,Tianfa Tang,Yu Wang,Siyuan Li,Meilin Tao,Hongliang Zhang,Liu Yang,Changjin Tang
The occurrence of NH 3 over-oxidation represents one intractable challenge for the effective application of NH 3 -SCR technology. Herein, a rational NO x activation strategy was innovatively proposed to counteract NH 3 over-oxidation during high temperature NH 3 -SCR. As a proof of concept, the hybrid catalyst of CeO 2 -ZSM-5 was explored. It was shown that the activity of CeO 2 in NH 3 -SCR was profoundly improved via physically mixing with ZSM-5, achieving more than 85 % NO at 500 °C, in sharp contrast to the negative NO conversion present for pristine CeO 2 . Comprehensive characterizations from NH 3 -TPD, NO-TPD and in situ DRIFTS verified the negligible modification of NH 3 oxidation but significant alteration of surface NO x . Due to the facile NO x activation, the reaction of NH 3 + NO x overwhelms that of NH 3 + O 2 , leading to the obtainment of excellent high temperature NH 3 -SCR performance. The novel strategy reported here is expected to provide valuable guidance for designing NH 3 -SCR catalysts with superior high temperature performance.
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
ACS Applied Nano Materials
·
2025
·
IF 5.5
Sajid Ali,Xingwen Cha,Jinxin He,Muhammad Ubaid Ali,Muhammad Junaid Aslam,Songbo Chen,Kok Bing Tan,Guowu Zhan
Tunable electronic properties of supported Cu/CeO2 catalysts are critical for improving the active site activity in catalysis. In this contribution, we propose a surface engineering protocol that utilizes unique ascorbic acid (AA) properties to generate surface defects and modify the electronic properties of Cu–Ce catalysts. This approach relies on forming abundant (Ce3+-Ov) defective sites on the CeO2 surface synthesized with a Ce-benzene-tricarboxylate metal–organic framework (MOF) as a precursor through AA adsorption. Subsequently, Cu sites can be effectively anchored onto the generated Ce3+-Ov, exhibiting excellent electronic transfer between (Ce3+-Ov/Ce4+ ↔ Cu2+/Cu+) CuCe, resulting in highly active Cu+ with well-balanced Ce3+-Ov defects. A high fraction of Cu+ with Ce3+-Ov was dedicated to the presence of AA. The resultant Cu/AA-MOF-CeO2 catalyst demonstrated outstanding performance toward CO oxidation (90–95 °C), being far superior to that of the conventionally prepared Cu/MOF-CeO2 catalyst (110–115 °C). In-depth characterizations confirmed that the remarkable performance was considerably related to the enhanced Cu–Ce interaction, enriched Cu+ active sites, and balanced Ce3+-Ov defects. This work highlights the potential of the Cu/AA-MOF-CeO2 catalyst as a sustainable solution for low-temperature catalytic CO oxidation reaction.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Bingcai Chen,Pengpeng Li,Bing Wang,Yingde Wang
CO sensor is helpful to monitor the working state of combustion equipment, such as industrial boilers and engines, and to ensure the production process and human life safety. However, balancing fast response/recovery and high response value for metal oxide CO sensors remains a challenge. In this work, based on band gap engineering, porous TiO 2 /CeO 2 NSs with different TiO 2 coupling amounts were prepared by hydrothermal method combined with flame annealing. The heterojunction composed of TiO 2 and CeO 2 narrowed the energy band width of the composite system and made the electron transmission more efficient, which endowed TiO 2 /CeO 2 NSs with good gas sensing properties. The results indicated that the response value of TiO 2 /CeO 2 NSs is 9.78 time that of CeO 2 NSs. Its ultrafast response/recovery time (2 s/6 s), good CO selectivity and wide CO monitoring range (500 ppb-5000 ppm) are also impressive. The TiO 2 /CeO 2 NSs sensor has great potential for rapid CO monitoring.
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
·
2023
·
IF 5.2
Chenghao Zhang,Chun Li,Xiaoqing Si,Jianwei Gao,Junlei Qi,Jian Cao
Cerium oxide (CeO 2 ) in the range of 0–16 mol.% is used to enhance the joint of Ag-based filler for brazing yttria-stabilized zirconia (YSZ) ceramic in the air. Ag–CeO 2 filler is first adopted to braze YSZ ceramic (3 mol.% yttria). The CeO 2 is found to cluster at the interface of YSZ and Ag seam, improving the wetting behavior of Ag-based fillers. The maximum shear strength of YSZ joints can reach 35.1 MPa using Ag–1CeO 2 fillers at 1050 °C/30 min. Moreover, CeO 2 is used to enhance the Ag–CuO filler for brazing YSZ ceramic. As the increase of CeO 2 content, the contact angle of Ag–CuO on the YSZ surface decreases first and then increases. The average shear strength could reach 76.5 MPa using Ag–CuO–8CeO 2 at 1050 °C/30 min. The CeO 2 could decrease residual stress by adjusting the linear expansion coefficient of Ag-based fillers. Therefore, this study provides a new strategy for exploring air brazing fillers.
研究领域:
材料科学
·
焊接技术
✓ 已验证
产品关联
DOI
高影响因子