CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Xixi Chen,Hai Yang,Chaktong Au,Shuanghong Tian,Ya Xiong,Yu Chang
Reduction of potential carcinogenic bromate formation is a big challenge for the application of ozone in the treatment of Br − -containing wastewater. Three CeO 2 nanocrystals individually with exposed (1 0 0), (1 1 0), and (1 1 1) facets were prepared and adopted as catalysts for the ozonation of Br − containing wastewater. It is found that faceted CeO 2 greatly inhibited the bromate formation and simultaneously enhanced the pollutant removal. The catalytic activity follows the order of (1 0 0) > (1 1 0) > (1 1 1). In the presence of CeO 2 (1 0 0), there is 71.4 ± 2.9% of sulfamethoxazole (SMZ) degradation (only 24.9 ± 1.8% in ozone alone). Moreover, the generation of bromate was reduced by 29.6%, 38.8%, 52.4%, 66.4%, respectively, when the initial Br − concentration is 1.0, 2.0, 34.0, 65.0 mg L −1 . Meanwhile, the antibacterial-active groups in most of the identified intermediates were destroyed and much lower biotoxicity of the treated wastewater is observed. The good reducibility and Lewis acidity of CeO 2 (1 0 0) favors the activation of ozone and the redox cycle of ceria. DFT calculations show that ozone facilely dissociates into surface O and O 2 through interaction with the (1 0 0) facet. It is demonstrated that O 2 − , its derivatives (i.e. OH and 1 O 2 ) and surface O are generated and get involved in SMZ degradation. It is noted that O 2 − also functions as a key reductant to convert Ce 4+ to Ce 3+ which reduce HBrO/BrO − and BrO 3 − to Br − and therefore inhibit the formation of bromate. These results indicate that CeO 2 (1 0 0) catalyzed ozonation is a promising advanced oxidation process for the treatment of Br-containing wastewater, and crystal facet engineering is an efficient strategy to enhance the catalytic performance.
研究领域:
环境科学
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催化化学
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理论计算
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2019
·
IF 7.65
Jing Wang,Xie Quan,Shuo Chen,Hongtao Yu,Guobin Liu
Heterogeneous catalytic ozonation, in which ozone is activated by various catalysts to produce reactive oxygen species (ROS), is an effective approach to degrade persistent organic pollutants in water. However, catalyst with high activity and good stability for catalytic ozonation still remains rare. In this work, a highly dispersed cerium oxide on oxidized carbon nanotubes (CeO 2 -OCNT) were prepared and characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and temperature-programmed reduction using hydrogen (TPR-H 2 ) experiments. The as-synthesized CeO 2 -OCNT showed significantly enhanced catalytic performance for degrading organic pollutants during catalytic ozonation. The removal efficiency of optimized CeO 2 -OCNT for phenol mineralization was 2–3 times of pure CeO 2 and OCNT, and was also better than that of a composite with the same composition, which demonstrated a synergic effect between OCNT and CeO 2 on CeO 2 -OCNT for catalytic ozonation. The TOC removal efficiency exhibited no obvious reduction after five cycling experiments, indicating the synthesized CeO 2 -OCNT possessed good reusability. Moreover, electron paramagnetic resonance (EPR) and radicals quenching experiments revealed that hydroxyl radicals ( OH) were the dominant ROS for organic pollutants degradation. The superior activity of CeO 2 -OCNT for catalytic ozonation could be attributed to the well-dispersed CeO 2 , the improved mass transfer, and the facilitated redox Ce 3+ /Ce 4+ cycling.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Sitong Liu,Shengli Niu,Hewei Yu,Kuihua Han,Sunwen Xia,Zihao Yang,Yue Zheng,Yujiao Zhang,Yanan Hao,Abulikemu Abulizi
The current transesterification for biodiesel is normally conducted with heat input and the resource is required to remove the contained water, which is complicated and costly. The novel magnetic catalyst of the bimetallic oxides of CeO 2 and Fe 3 O 4 supported on the hierarchical pore ZSM-5 was prepared and used for the biodiesel production through transesterification of palm oil with methanol under the electrolytic assistance. The prepared catalysts were characterized by SEM-EDS, TEM, FTIR, XRD, CO 2 /NH 3 -TPD, N 2 adsorption–desorption and VSM, etc. The loaded cerium stimulated the particles growth and abundant catalytic active sites were obtained due to the coral-like structure and they were beneficial for transesterification. The presence of both acidic and basic sites guaranteed the strong catalytic capability of the CeO 2 /ZSM-5@Fe 3 O 4 catalyst. Under the optimized transesterification condition of the catalyst dosage of 3 wt%, methanol to oil molar ratio of 18:1, reaction time of 2.5 h, electrolysis voltage of 40 V, presence of 2 % wt/wt of water added and reaction temperature of 25 ℃, the FAME yield of approximately 95 % was achieved. Also, the catalyst showed an acceptable reusability, where the FAME yield of 79 % was obtained after fourth reused cycle. In conclusion, the water in the resource promotes the electrolytic transesterification to occur efficiently at the room temperature.
研究领域:
化学工程
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可再生能源
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2018
·
IF 4.229
Lijian Wang,Yanqun Zhu,Hui Yang,Yong He,Jun Xia,Yanwei Zhang,Zhihua Wang
The effect of several catalyst supports with large specific surface area (such as SiC, Al 2 O 3 , SiC–Al 2 O 3 –ball, and SiC–Al 2 O 3 ) on catalytic activity was evaluated in this study. CuO–CeO 2 supported on SiC–Al 2 O 3 exhibited high stability and activity, which was considerably close to the thermodynamic equilibrium curve at 625 °C during the stability test for 50 h. The SO 3 decomposition temperature decreased from 750 °C to 625 °C. SiC–Al 2 O 3 contained numerous micropores and mesopores and had a large specific area, indicating strong adsorption, as determined by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and nitrogen adsorption measurement. X-ray photoelectron spectroscopy (XPS) revealed that the surface of SiC–Al 2 O 3 consisted of Al 2 O 3 , SiC, and SiO 2 and that the cerium oxide surface had the largest number of defects. Temperature-programmed reduction (H 2 -TPR) results indicated that the cerium–copper oxides on the surface of powdered SiC–Al 2 O 3 had the strongest redox potential and that CuO had the lowest reduction temperature.
研究领域:
化学工程
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2018
·
IF 3.794
Jinshuang Wang,Junbin Sun,Qiangshan Jing,Bing Liu,Hao Zhang,Yu Yongsheng,Jieyan Yuan,Shujuan Dong,Xin Zhou,Xueqiang Cao
The properties of ZrO 2 co-stabilized by CeO 2 and TiO 2 ceramic bulks were investigated for potential thermal barrier coating (TBC) applications. Results showed that the (Ce 0.15 Ti x )Zr 0.85-x O7 (x = 0.05, 0.10, 0.15) compositions with single tetragonal phase were more stable than the traditional 8YSZ at 1573 K. These compositions also showed a large thermal expansion coefficient (TEC) and a high fracture toughness, which were comparable to those of YSZ. However, the phase stability, fracture toughness and sintering resistance of the CeO 2 -TiO 2 -ZrO 2 system showed a decline tendency with the increase of TiO 2 content. The TEC of the ceramic bulks decreased with increase of TiO 2 content as well because the crystal energy was enhanced with increasing substitution of Zr 4+ by smaller Ti 4+ . The (Ce 0.15 Ti 0.05 )Zr 0.8 O 2 had the best comprehensive properties among the (Ce 0.15 Ti x )Zr 0.85-x O 2 compositions as well as a low thermal conductivity . Therefore, it can be explored as a TBC candidate material for high-temperature applications.
研究领域:
材料科学
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热力学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
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2017
·Vol. 83
·期 2
·308-314
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IF 1.575
Wang Li,Li Yanhong,Shi Min,Ma Wenle,Cui Hongtao
Abstract In this work, nanosphere-like and nanowire shaped CeO 2 nanocrystals were prepared at room temperature utilizing the epoxide precipitation reaction in aqueous and ethanolic solutions. It was found that the shape of CeO 2 nanocrystals depends on the reaction kinetics of epoxide in solution. The isotropic growth of nanocrystals in aqueous solution resulted in the formation of CeO 2 nanocrystals with sphere-like shape, while the anisotropic growth of nanocrystals in ethanolic solution led to the nanowire shape of CeO 2 nanocrystals. The anisotropic growth of nanocrystals was attributed to the high surface energy of their {110} facet induced from the active reaction of epoxide in ethanolic solution. The reaction kinetics of epoxide affected not only the size and crystallinity of CeO 2 nanocrystals, but also their shape. As a result, the produced CeO 2 nanocrystals had different electrochemical performance. As an electrode material for application in supercapacitor, the nanosphere-like CeO 2 nanocrystals presented better electrochemical performance and longer cycle life than the packed CeO 2 nanowires. Graphical Abstract Nanosphere-like and nanowire shaped CeO2 nanocrystals were prepared utilizing the epoxide precipitation reaction in aqueous and ethanolic solutions. It was found that the shape of CeO2 nanocrystals depends on the reaction kinetics of epoxide in solution. The isotropic growth of nanocrystals in aqueous solution produced CeO2 nanocrystals with sphere-like shape, while the anisotropic growth of nanocrystals in ethanolic solution produced nanowire shaped CeO 2 . As an electrode material for application in supercapacitor, the nanosphere-like CeO 2 nanocrystals presented better electrochemical performance and longer cycle life than the packed CeO 2 nanowires.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2023
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IF 6.9
Jiawen Chen,Qingjie Meng,Feng Bi,Jingkun Chen,Xiaole Weng,Zhongbiao Wu
Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds (VOCs) originating from solvent-based industrial processes. The varied composition tends to influence each VOC's catalytic behavior in the reaction mixture. We investigated the catalytic destruction of multi-component VOCs including dichloromethane (DCM) and ethyl acetate (EA), as representatives from pharmaceutical waste gases, over co-supported H x PO 4 -RuO x /CeO 2 catalyst. A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA's superior adsorption capacity. Preferential adsorption of EA on acidic sites (H x PO 4 /CeO 2 ) promoted DCM activation on basic sites (O 2− ) and the dominating EA oxidation blocked DCM's access to oxidation centers (RuO x /CeO 2 ), resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation. The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products, leading to increased gaseous by-products such as acetic acid originating from EA pyrolysis. Notably, DCM at low concentration slightly promoted EA conversion at low temperatures with or without water, consistent with the enhanced EA adsorption in co-adsorption analyses. This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity. Moreover, water benefited EA hydrolysis but decreased CO 2 selectivity while the generated water derived from EA was likely to affect DCM transformation. This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Jiabing Chen,Yibo Tang,Xingmao Jiang,Rui Zhang,Xiaojun Lu
In this work, Ru–CeO2 prepared by a “melting” method and used as a heterogeneous catalyst for ethylene methoxycarbonylation was investigated, together with two other catalysts prepared by impregnation and aerosol methods. The Ru–CeO2 (1%-M) catalyst demonstrates activity significantly higher than that of the other catalysts with the same Ru content. The XPS and Raman analysis results suggest that the Ru–CeO2 (1%-M) oxygen vacancy content is not the highest among the catalysts prepared using the three methods, even though the content oxygen vacancies have been reported to play a crucial role in carbonylation when using a Ru–CeO2 catalyst. It was discovered that the available Ru0 (Ru0 in the freshly prepared sample plus that being transformed from Run+ during reduction) is the other decisive factor in determining the catalyst’s performance. We further investigated the high reducibility of the catalyst prepared by using the melting method and discovered that a weak metal–support interaction could be obtained because of the independent formations of Ru and CeO2 crystals with graphite carbon as the barrier. Removing carbon under the optimal conditions could facilitate the as-formed Ru crystals anchored onto CeO2; therefore, there is no strong interaction between Ru and CeO2.
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
JOURNAL OF RARE EARTHS
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2020
·
IF 3.104
Xiangcheng Shi,Jingjie Yang,Xintong Wen,Fuli Tian,Changyan Li
Cerium oxide-based nanozymes have recently drawn much attention in the field of biomedical and antioxidant applications, because of their unique regenerative or autocatalytic properties. Herein, we studied the biomimetic superoxide dismutase (SOD) nanozymes CeO 2 -Gd that combines the fluorescence properties of rare earth Gd with the antioxidant properties of CeO 2 nanoparticles , which was prepared via facile route. The structure and composition of the CeO 2 -Gd were measured and verified by X-ray powder diffraction (XRD), Raman spectroscopy , transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray electron spectroscopy (XPS). Confocal microscopy was used to image cells. Antioxidant performance and cell viability of these nanozymes were measured in vitro using BGC-803 cell. CeO 2 -Gd nanozymes with a higher Ce 3+ /Ce 4+ ratio show higher superoxide dismutase (SOD) mimetic activity. Their antioxidant activity and fluorescence properties of CeO 2 -Gd in BGC-803 cancer cells are enhanced by oxygen vacancies generated by doping rare-earth elements Gd. This work may guide the future design of CeO 2 -Gd-based biomimetic nanozymes for anticancer and antioxidant applications.
研究领域:
纳米技术
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生物医学工程
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材料科学
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生物化学
·
细胞生物学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Xueli Mei,Xueyang Zhao,Hongtao Xie,Nemanja Gavrilov,Qin Geng,Qin Li,Huawei Zhuo,Yali Cao,Yizhao Li,Fan Dong
The electrocatalytic two-electron oxygen reduction reaction (2e-ORR) represents one of the most prospective avenues for the in situ synthesis of hydrogen peroxide (H2O2). However, the four-electron competition reaction constrains the efficiency of H2O2 synthesis. Therefore, there is an urgent need to develop superior catalysts to facilitate the H2O2 synthesis. In this study, graphite-phase carbon nitride and cerium dioxide composites (g-C3N4/CeO2) with varying CeO2 loadings were prepared with favorable 2e-ORR electrocatalysts. The optimized composite, containing 20 wt % CeO2 (g-C3N4/CeO2-20%) exhibited the highest Faradaic efficiency (FE) of 97% and notable H2O2 yielding of 9.84 mol gcat.–1 h–1 at the potential of 0.3 V (vs RHE) in a 0.1 M KOH electrolyte. Density functional theory calculations revealed that the improvement of the selectivity and yield of H2O2 for the composites were attributed to the charge transfer between g-C3N4 and CeO2, which causes the active site C atom donating electrons to form C+, thereby enhancing the adsorption and desorption of *OOH intermediates. Additionally, the g-C3N4/CeO2-20% composite exhibits excellent 2e-ORR performance in neutral and acidic electrolytes and demonstrates superior capability in electro-Fenton degradation of organic pollutants. This study not only provides new insights into the electrocatalytic mechanism of g-C3N4/CeO2 composites but also demonstrates an effective method for designing 2e-ORR catalysts.
研究领域:
材料科学
·
电化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainable Energy & Fuels
·
2025
·
IF 4.1
Jiale Shang,Tong Wei,Xiaoqing Yan,Zheng Fang,Leilei Du,Jichao Shi,Fozia Sultana,Tongtong Li,Renhong Li
Urea-assisted water splitting represents a prospective approach for sustainable hydrogen (H2) production. However, the challenge of designing highly efficient, durable, and economically viable bifunctional electrocatalysts hampers the practical implementation of this technology. In this work, we design a Ni3S2-CeO2 heterostructure catalyst on nickel foam, tailored to upgrade the efficiency and cost-effectiveness of urea-assisted electrolysis. The catalyst features a unique interconnected nanosheet architecture, which boosts its activity, obtaining 100 mA cm−2 for the urea oxidation reaction (UOR) with an overpotential of just 146 mV, and only 56 mV at 10 mA cm−2 for the hydrogen evolution reaction (HER). When employed at both electrodes in a urea electrolysis electrolyzer, the Ni3S2-CeO2/NF catalyst reaches a high current density of 500 mA cm−2 at 1.734 V. Experimental results and DFT calculations demonstrate that the Ni3S2-CeO2/NF heterogeneous interface facilitates electron redistribution and increases electronic density at Fermi level, thereby enhancing the conductivity. The incorporation of CeO2 facilitates the Ni3S2 surface reconstruction, forming NiOOH active species with abundant oxygen vacancies (OV) that optimize urea adsorption and improve UOR kinetics. Additionally, CeO2 reduces the hydrogen adsorption energy (ΔGH*), accelerating the HER process. These synergistic effects endow the Ni3S2-CeO2/NF catalyst to achieve outstanding bifunctional activity in UOR and HER, underscoring its potential for efficient urea-assisted electrolysis with low overpotentials at high current densities. This investigation supplies guidance for creating effective bifunctional catalysts for sustainable hydrogen production.
研究领域:
材料科学
·
电化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Xiaocong Qin,Qi Xue,Changluo Su,Yuan Dang,Xiaoqin Sun,Yuanzhen Zhou
Catalytic oxidation is an efficient method for mitigating toluene emissions, but enhancing catalytic performance for toluene oxidation remains a challenge. To enhance the oxidation capacity of catalysts, appropriate morphology and composition adjustments are required. Herein, the porous CeO 2 -Co 3 O 4 hybrid nanosheets (CeO 2 -Co 3 O 4 HNSs) have been designed and prepared by the hydrothermal method . Compared with single composition CeO 2 and Co 3 O 4 , the CeO 2 -Co 3 O 4 HNSs exhibit superior performance, achieving a remarkable 90% toluene conversion at a reaction temperature of 215°C with a space velocity of 36,000 mL/(h·g). Their enhanced activity can be attributed to the unique morphology and multi-component synergistic effect. The introduction of Co can significantly increase the content of oxygen vacancy and optimize the electronic structure, which can enhance the formation of surface-active oxygen and accelerate the cycle of the Ce 3+ /Ce 4+ redox pair. This work establishes a promising avenue for treating volatile organic compounds in exhaust emissions.
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
危险品化学品经营许可证（带存储）