APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Shibo Yu,Yiqing Zeng,Mengna Zhan,Shule Zhang,Zhaoxiang Zhong
The influence of phosphorus (P) on ammonia selective catalytic reduction (NH 3 -SCR) catalysts has been the subject of considerable scrutiny. Nevertheless, the precise mechanism of its influence remains a matter of contention. Furthermore, the impact of introducing P at varying stages during catalyst preparation process and its different sites within the catalyst structure on performance is frequently disregarded, significantly hindering practical guidance for designing effective modified catalysts. In this study, a series of P-modified CeO 2 /TiO 2 catalysts were synthesized by introducing P at different preparation stages, and various of characterization and comparison experiments were conducted to elucidate the effect of introducing P at different stages on NH 3 -SCR performance of NO x . Results show that introducing P before loading CeO 2 boosts catalyst activity, whereas delaying the introduction of P results in decreased activity and a progressive decline in catalyst performance as the sequence of P introduction is postponed. P introduced earlier tends to be distributed on the surface of the TiO 2 support, which contributes to the dispersion and anchoring of Ce species. In contrast, when the introduction of P was delayed, it tended to be distributed on the surface of the active species, which led to pore plugging and active sites being covered. Secondly, the variation in loading sites resulting from alterations in the stage of P introduction significantly affected on the chemical environment of Ce species, leading to notable differences in the redox capacity of the catalysts. This is the primary reason for the considerable discrepancy in the SCR performance of the catalysts. This study revealed the sensitivity of the stage of P introduction to CeO 2 /TiO 2 catalysts, providing new insights for designing modified CeO 2 /TiO 2 catalysts.
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
Catalysts
·
2021
·Vol. 11
·期 4
·445
·
IF 4.146
Yangyang Guo,Xiaofei Xu,Hong Gao,Yang Zheng,Lei Luo,Tingyu Zhu
Ca poisoning behavior is inevitable for high-calcium content flue gas, so V2O5-WO3/TiO2(VWT) and V2O5-WO3-CeO2/TiO2(VWCeT) catalysts with different vanadium content have been prepared and the Ca-doped catalysts are compared in this manuscript. The result shows Ce addition can both promote the NO conversion and the alkali resistance. Lower Ca addition for 0.1VWCeT catalyst promotes its oxidability and Ce modification is more suitable for low vanadium catalysts. The total acidity and the reducibility of catalysts decline after Ca doping, and the reducibility of the active species on catalysts has been strengthened by Ce addition. CeO2based catalysts with lower Ca loading struggle to resist sulfur poisoning, while higher Ca loading favors SO2adsorption and also physically reduces the cerium acidification process. In the presence of SO2, additional Brønsted acid sites are formed in Ca rich catalyst. The dynamic NH3adsorption has been investigated, shows that Ca doping content on catalyst is critical for SCR reaction, and the catalyst is more susceptible to SO2initially in alkali flue gas during the actual application, but the sulfur resistance may increase with the alkali-poisoning effect aggravated by Ca doping.Keywords:Ca-poisoning;SCR reaction;NO reduction;V2O5-WO3/TiO2and V2O5-WO3-CeO2/TiO2catalysts;SO2and water;NO removal efficiency
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
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2017
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IF 2.986
Hualin Jiang,Menglin Li,Jun Liu,Xueqin Li,Lei Tian,Pinghua Chen
In this study, a novel CeO 2 -TiO 2 nanocomposite denoted as CeO 2 -3TiO 2 was successfully synthesized via a facile one pot hydro-thermal method without alkali. It exhibits high photocatalytic reduction reactivity toward Cr(VI) under visible light. The photocatalytic reactivity of CeO 2 -3TiO 2 is 18 times higher than that of pure CeO 2 , 28 times higher than pure TiO 2 , 15 times higher than the sample of simply mixed CeO 2 and TiO 2 . The solution with Cr(VI) initial concentration of 2780 ppb can be fast photoreduced by CeO 2 -3TiO 2 in 60 min under visible light to meet the criterion of U.S. Environmental protection Agency. Characterization results indicate CeO 2 -3TiO 2 has the good crystal form of heterojunction structure, narrow pore size distribution , narrow energy gap and high photogenerated electron-hole separation efficiency. Based on the experimental results, a speculated photocatalytic mechanism was proposed.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
PHYSICA SCRIPTA
·
2023
·Vol. 98
·期 11
·115027
·
IF 2.9
Deyang Ning,Jiaxiong He,Junqi Li,Zuoyu Liu,Renjie Liao,Yuanpei Lan,Fan Wang,Zhou Zou
In this work, three synthesis methods including photo-chemical, precipitation and hydrothermal were applied for synthesizing CeO2/TiO2 catalysts, and the catalytic performance including photodegradation degrees for organic pollutant and ammonia selective catalytic reduction (NH3-SCR) for NO removal were investigated. It was found that the photo-chemical synthesized CeO2-TiO2-PC exhibited the best photodegradation ability for methylene blue (MB), which had the degradation ratio of 91.21% and was approximately 23.92% higher than that with the matrix of rutile TiO2. The formed Ce-Ti heterojunction enhanced the separation of e−/h+ and further promoted the photocatalytic properties. Moreover, the CeO2-TiO2-PC, and the CeO2-TiO2-P which synthesized by the precipitation method showed better NH3-SCR properties than that of hydrothermal synthesized CeO2-TiO2-H below 300 °C, while the CeO2-TiO2-H owned an outstanding NH3-SCR performance above 300 °C. The difference on the NH3-SCR properties may be major attributed to the acid sites, pore structures and surface areas on the surface of different catalysts.
研究领域:
环境科学
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材料科学
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催化
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2017
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IF 3.133
Jingyi Bai,Xiaolu Sun,Gui Han,Guowang Diao
A new double-shell hollow structured material with high light harvesting and dye loading level for dye-sensitized solar cells (DSSCs) were synthesized via a one-pot hydrothermal method . When coated with TiO 2 shell, a hybrid double-shell CeO 2 @TiO 2 hollow sphere (D-CeO 2 @TiO 2 ) was performed as scattering layer in dye-sensitized solar cells, which further increase conversion efficiency from 5.27% of bare TiO 2 electrode to 7.95%. The enhancement is due to the high dye loading capacity of double shell CeO 2 hollow spheres core and high electron transport capacity of TiO 2 shell. Our work provides a feasible strategy for preparing multi-shell hollow spheres as scattering layers for high performance solar cells.
研究领域:
材料科学
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纳米技术
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太阳能
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
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IF 5.9
Lei Chen,Zhichun Si,Xiaodong Wu,Duan Weng
A CuO–CeO2–TiO2 catalyst for selective catalytic reduction of NOx with NH3 (NH3-SCR) at low temperatures was prepared by a sol–gel method and characterized by X-ray diffraction, Brunner–Emmett–Teller surface area, ultraviolet–visible spectroscopy, H2 temperature-programmed reduction, scanning electron microscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). The CuO–CeO2–TiO2 ternary oxide catalyst shows excellent NH3-SCR activity in a low-temperature range of 150–250 °C. Lewis acid sites generated from Cu2+ are the main active sites for ammonia activation at low temperature, which is crucial for low temperature NH3-SCR activity. The introduction of ceria results in increased reducibility of CuO species and strong interactions between CuO particles with the matrix. The interactions between copper, cerium and titanium oxides lead to high dispersion of metal oxides with increased active oxygen and enhanced catalyst acidity. Homogeneously mixed metal oxides facilitate the “fast SCR” reaction among Cu2+–NO, nitrate (coordinated on cerium sites) and ammonia (on titanium sites) on the CuO–CeO2–TiO2 catalyst at low temperatures.
研究领域:
环境催化
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材料化学
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表面科学
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化学工程
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大气污染控制
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
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2020
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IF 5.778
Qiyuan Chen,Lu Liu,Lifen Liu,Yizhen Zhang
Emissions of volatile organic compounds (VOCs) air pollutants could worsen air quality and adversely affect human health, thus developing more efficient low-temperature VOCs removal techniques is desired. A novel continuous system integrating UV-assisted photo-electrochemical catalysis with microbial fuel cell (UV-assisted PEC-MFC) has been established for promoting removal of gaseous ethyl acetate or toluene and generating electricity simultaneously. In this system, CeO 2 /TiO 2 /ACF catalytic cathode is prepared and used for combination with bio-anode for accelerating cathodic reaction . This UV-assisted PEC-MFC system exhibits an excellent elimination capacity (EC) of ethyl acetate (∼0.39 g/m 3 , EC: ∼2.52 g/m 3 /h) or toluene (∼0.29 g/m 3 , EC: 1.89 g/m 3 /h) under close-circuit condition. Furthermore, an outstanding elimination capacity (EC: 28.04 g/m 3 /h) for high concentration toluene (∼4.10 g/m 3 ) removal is obtained after toluene gas passes sequentially through the catalytic cathode then the bio-anode. This way of PEC degradation and biodegradation, avoids inhibition of exoelectrogens activity from toxicity of high concentration toluene. Simultaneously, the cell voltage of UV-assisted PEC-MFC system is stable at 0.11 V (vs. SCE) and 1.452×10 −4 kWh is generated from treatment of toluene gas stream in 6 h duration time. The possible mechanism of VOCs removal in this novel system has been proposed and discussed. This study provides new technical basis for treating gaseous pollutants via integrating photo-electrochemical catalysis with electricity generating microbial fuel cell for energy conversion.
研究领域:
环境科学
·
生物技术
✓ 已验证
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
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2021
·
IF 10.618
Zhenxing Wang,Hongli Zhao,Qianmei Gao,Kaicha Chen,Minbo Lan
Here we presented a new facile strategy to fabricate ultrathin two-dimensional (2D) metal oxide nanosheets , by using polydopamine-coated graphene (rGO@PDA) as a template under simply wet-chemical conditions. Based on the strategy, graphene-like CeO 2 –TiO 2 mesoporous nanosheet ( MNS-CeO 2 -TiO 2 ) was prepared and was loaded with dispersive Ag nanoparticles (AgNPs) to obtain effective electrocatalysts (denoted as Ag/MNS-CeO 2 -TiO 2 ) for electrochemical detection of superoxide anion (O 2 •− ). Characterizations demonstrated that MNS-CeO 2 -TiO 2 exhibited ultrathin thickness, larger specific surface area, and pore volume in comparison with its bulk counterpart. The above properties of MNS-CeO 2 -TiO 2 shorten electron transmission distance, promotes mass transfer, and is conducive to the dispersion of post-modified AgNPs. Therefore, the recommended Ag/MNS-CeO 2 -TiO 2 sensors (denoted as Ag/MNS-CeO 2 -TiO 2 /SPCE ) exhibited satisfactory properties, including the sensitivity of 737.1 μA cm −2 mM −1 , the detection limit of 0.0879 μM (S/N = 3), and good selectivity. Meanwhile, the sensors also successfully realized in the online monitoring of O 2 •− released from HepG2 cells, meaning the prepared sensors had practical application potential towards the analysis of O 2 •− in biological samples.
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
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
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2022
·
IF 18.027
Ting Wang,Liang Chen,Cong Chen,Mengtian Huang,Youju Huang,Shoujie Liu,Benxia Li
Photocatalytic CO2 conversion into a high-value-added C2 product is a highly challenging task because of insufficient electron deliverability and sluggish C–C coupling kinetics. Engineering catalytic interfaces in photocatalysts provides a promising approach to manipulate photoinduced charge carriers and create multiple catalytic sites for boosting the generation of C2 product from CO2 reduction. Herein, a Cuδ+/CeO2-TiO2 photocatalyst that contains atomically dispersed Cuδ+ sites anchored on the CeO2-TiO2 heterostructures consisting of highly dispersed CeO2 nanoparticles on porous TiO2 is designedly constructed by the pyrolytic transformation of a Cu2+-Ce3+/MIL-125-NH2 precursor. In the designed photocatalyst, TiO2 acts as a light-harvesting material for generating electron–hole pairs that are efficiently separated by CeO2-TiO2 interfaces, and the Cu–Ce dual active sites synergistically facilitate the generation and dimerization of *CO intermediates, thus lowering the energy barrier of C–C coupling. As a consequence, the Cuδ+/CeO2-TiO2 photocatalyst exhibits a production rate of 4.51 μmol–1·gcat–1·h–1 and 73.9% selectivity in terms of electron utilization for CO2 to C2H4 conversion under simulated sunlight, with H2O as hydrogen source and hole scavenger. The photocatalytic mechanism is revealed by operando spectroscopic methods as well as theoretical calculations. This study displays the rational construction of heterogeneous photocatalysts for boosting CO2 conversion and emphasizes the synergistic effect of multiple active sites in enhancing the selectivity of C2 product.
研究领域:
化学
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材料科学
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环境科学
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催化
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2019
·
IF 2.722
Manoj Pudukudy,Qingming Jia,Jingyou Yuan,Sivagnanam Megala,Ramesh Rajendran,Shaoyun Shan
A single-pot surfactant-free sol-gel method is reported for the facile and bulk synthesis of ultrafine-nanospherical CeO 2 /TiO 2 composites with different CeO 2 loadings and their photocatalytic-activity for the degradation and mineralization of tetracycline (TC) under visible-light irradiation is investigated for the first time. The incorporation of CeO 2 favored the controlled crystalline growth of TiO 2 in its anatase phase, and their crystallinity and particle size were significantly decreased. The textural and optical properties of TiO 2 were also improved with the incremental addition of CeO 2 by increasing their specific surface-area and visible-light absorption respectively. The optical band gap of TiO 2 decreased to 2.24 eV with the incorporation of 1% CeO 2 and it further decreased to 2.21 eV with the incremental amount of CeO 2 . Due to the formation of heterojunction in the composite, the recombination rate of electron-hole pairs was significantly decreased. A highest TC removal efficiency of ~99% was observed for 4% CeO 2 /TiO 2 composite for a period of 80 min of visible-light irradiation. Moreover, 88.2% TC mineralization efficiency was achieved for a period of 240 min of visible light irradiation. The enhanced catalytic-activity could be attributed to the synergy of high degree of adsorption followed by an enhanced photocatalysis at the heterointerface formed by the adjacent contact between TiO 2 and CeO 2 . The synergistic effects of low-particle size, high surface-area, enhanced visible-light absorption, reduced band-gap, and increased life-time of the photogenerated charge-carriers through the formation of heterointerface contributed to its high photocatalytic activity. The hydroxyl and superoxide-anion radicals played a superior role in the photocatalytic process. Moreover, the composites retained its efficiency for seven-cycles of reaction without any significant-loss in its activity and structural and textural stability.
研究领域:
材料科学
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环境催化
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纳米材料化学
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光催化
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水污染治理
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功能材料
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表面与界面化学
✓ 已验证
DOI
高影响因子
ADVANCED COMPOSITE MATERIALS
·
2025
·
IF 2.3
Zhiwei Cai,Jing Sun,Ning Jiang,Chao Chen,Yanzi Lin,Yimin Shen,Minmin Ge,Guanglin Fang,Corinne Boudon,Yaokang Lv,Laurent Ruhlmann
Novel Ce/TiO2 were synthesized using a solution-based method involving two types of Ce(III)-doped polyoxotitanium cages, namely ([Ti28O38(OEt)38CeCl(EtOH)1.4] and [Ti8O7(OEt)21Ce(EtOH)]). This novel material was used to coat the surface of polyvinylidene chloride (PVDC)/polyvinyl chloride (PVC) film, resulting in a homogeneous CeO2/TiO2@PVDC/PVC film. Remarkably, the CeO2/TiO2@PVDC/PVC film exhibited notable hydrophobicity and UV absorption capacity. Furthermore, the UV absorption capacity of the films was significantly improved with increasing CeO2/TiO2 content. The incorporation of CeO2/TiO2 also led to a substantial improvement in the barrier properties of the film, particularly in terms of water vapor permeability. These modified films hold great potential and offer a wide range of applications in the pharmaceutical packaging and food packaging industries.
研究领域:
材料科学
·
纳米技术
·
高分子科学
·
包装工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2019
·
IF 2.846
Lei Chen,Ding Wang,Jiadao Wang,Duan Weng,Li Cao
The CeO 2 -TiO 2 (CeTi) and CeO 2 /WO 3 -TiO 2 (CeWTi) catalysts were prepared by sol-gel method. The as-prepared catalysts were hydrothermally treated at 760 °C for 48 h in air containing 10 vol% H 2 O to obtain the hydrothermal aged catalysts. The sulfur aged catalysts were treated at 400 °C with 100 ppm SO 2 , 10% water vapor, air balance for 48 h and catalysts. The powder X-ray diffraction (XRD) and Raman results indicate that the crystallization of hydrothermal aged catalysts is more serious than sulfur aged catalysts. In addition, tungsten species can stabilize the CeTi catalyst from grain growth. According to the results of in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS), temperature-programmed desorption of ammonia (NH 3 -TPD), H 2 temperature-programmed reduction (H 2 -TPR) and ammonia oxidation , the aging process leads to loss of surface area, redox properties, surface acidities and surface ceria concentration, especially for the hydrothermal aging. The NH 3 -NO/NO 2 SCR performances of sulfur aged catalysts are better than that of hydrothermal aged catalysts. Compared with CeTi catalyst, the addition of tungsten inhibits the crystallization of catalyst. So that more acid sites and active sites are retained. This is also the reason why tungsten addition improves the NH 3 -NO/NO 2 SCR performance of CeTi catalyst.
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
危险品化学品经营许可证（带存储）