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| 1 | Low-temperature SCR activity and SO_2 deactivation mechanism of Ce-modified V_2O_5–WO_3/TiO_2 catalyst显示文摘The promotion effect of ceria modi fi cation on the low-temperature activity of V2O5-WO3/TiO2 catalyst was evaluated for the selective catalytic reduction of NO with NH3(NH3-SCR). The catalytic activity of 1 wt% V2O5-WO3/TiO2 was signi fi cantly enhanced by the addition of 8 wt%ceria, which exhibited a NO x conversion above 80% in a broad temperature range 190–450 1C. This performance was comparable with 3 wt%V2O5-WO3/TiO2, indicating that the addition of ceria contributed to reducing the usage of toxic vanadia in developing low-temperature SCR catalysts. Moreover, V1 Ce WTi exhibited approximately 10% decrease in NOx conversion in the presence of 60 ppm SO2. The characterization results indicated that active components of V, W and Ce were well dispersed on TiO2 support. The synergetic interaction between Ce and V species by forming V–O–Ce bridges enhanced the reducibility of VCe WTi catalyst and thus improved the low-temperature activity. The sulfur poisoning mechanism was also presented on a basis of the designed TPDC(temperature-programmed decomposition) and TPSR(temperatureprogrammed surface reaction) experiments. The deposition of(NH4)2SO4on V1 Ce WTi catalyst was much smaller compared with that on V1 Ti.On the other hand, the oxidation of SO2 to SO3was signi fi cantly promoted on the CeO2-modi fi ed catalyst, accompanied by the formation of cerium sulfates. Therefore, the deactivation of this catalyst was mainly attributed to the vanishing of the V–Ce interaction and the sulfation of active ceria. | Ziran Ma Xiaodong Wu Ya Feng Zhichun Si Duan Weng Lei Shi | 2015 | Progress in Natural Science:Materials International2015，25，4： | 29 |
| 2 | 氧化铈纳米粒子光催化降解亚甲基蓝的动力学和机理(英文)显示文摘CeO2 nanocrystals were synthesized by a simple precipitation method and calcination at 600℃.(NH4)2Ce(NO3)6 and ammonia were used as precursors.The CeO2 nanoparticles were characterized by X-ray diffraction,Fourier transform infrared spectroscopy,transmission electron microscopy,and N2 adsorption.The photodegradation of methylene blue catalyzed by CeO2 nanoparticles was studied under UV and sunlight irradiation.The highest degradation was obtained with 1.0 g/L CeO2 at pH 11 within 125 min.The pseudo first order rate constants of dye bleaching were calculated as 16.2×10-3 and 15.7×10-3 min-1 under UV and sunlight irradiation,respectively.The effect of iso-PrOH,iodide ion,and H2O2 was studied to predict the pathway of dye degradation.The obtained results indicate the effect of photogenerated holes in the degradation mechanism of the dye.Also,the photocatalytic activity of the prepared photocatalyst was studied in the presence of several negative ions. | H.R.POURETEDAL A.KADKHODAIE | 2010 | 催化学报2010，31，11： | 16 |
| 3 | Fabrication of highly efficient heterostructured Ag-CeO2/g-C3N4 hybrid photocatalyst with enhanced visible-light photocatalytic activity显示文摘On the basis of hydrothermal synthesis of Ag-CeO2 microspheres,Ag-CeO2/g-C3N4 composite photocatalyst with heterostructure was prepared by simple solvent evaporation of Ag-CeO2 and g-C3N4.To characterize the composition,structure,morphology and light absorption properties of the as-prepared Ag-CeO2/g-C3N4 composites,XRD,FTIR XPS,SEM,TEM,PL,BET and UV-vis DRS were used,respectively.The as-prepared photocatalyst was subjected to photocatalytic degradation of pollutants,and the prepared composite material has excellent photocatalytic activity for photodegradation of methylene blue(MB).The research shows that the photocatalytic properties of Ag-CeO2/g-C3N4 composites were related to the mass ratio of Ag-CeO2 microspheres and g-C3N4 nanosheets.When the ratio of Ag-CeO2 microspheres:g-C3N4 is 1:5,the composites have the highest photocatalytic activity,which was 9.6 and 3.3 times that of single Ag-CeO2 and g-C3N4,respectively.The improvement of photocatalytic activity is attributed to the heterostructure between the composite materials and the addition of noble metal silver,and the degradation of methylene blue by the visible light irradiation material is greatly improved.Finally,an attempt was made to analyze the principle of photocatalytic degradation of pollutants in prepared materials. | Chengbao Liu Dongxing Mao Jian Pan Junchao Qian Wenya Zhang Feng Chen Zhigang Chen Yenan Song | 2019 | Journal of Rare Earths2019，37，12： | 7 |
| 4 | Effect of synthesis time on morphology of CeO2 nanoparticles and Au/CeO2 and their activity in oxidative steam reforming of methanol显示文摘Ceria(CeO2)supports,synthesized by hydrothermal treatment with different synthesis time(CeO2-X h,where X is the synthesis time in h)in the presence of the surfactant cetyltrimethyl ammonium bromide,were used as supports for gold(Au)catalysts.The synthesis time significantly affects the morphological structure and crystallite size of CeO2,where CeO2-2 h has the smallest crystallite size with coexisting nanorods and nanoparticles.Transmission electron microscopy analysis confirms the morphology of CeO2 with distinctive(110),(100)and(111)planes,in agreement with interplanar spacings of 0.19,0,27 and 0.31,respectively.However,the morphology of CeO2-8 h and CeO2-48 h is mainly a truncated octahedral with crystal planes(111)and(100)accompanied by an interplanar spacing of 0.31 and0.27 nm,respectively.The CeO2-X h supports and those with a 3 wt%Au loading(Au/CeO2-X h)were investigated in the oxidative steam reforming of methanol at temperatures between 200 and 400℃.The Au/CeO2-2 h gave the highest methanol conversion level and hydrogen yield at a low temperature of 250℃.This superior catalytic performance results from the good interaction between the metal and support and the well-distributed Au species on the CeO2 support. | Srisin Eaimsumang Sujitra Wongkasemjit Sangobtip Pongstabodee Siwaporn Meejoo Smith Sukritthira Ratanawilai Nuwong Chollacoop Apanee Luengnaruemitchai | 2019 | Journal of Rare Earths2019，37，8： | 6 |
| 5 | Catalytic combustion of soot over Ru-doped mixed oxides catalysts显示文摘We employed modified substrates as outer heterogeneous catalysts to reduce the soot originating from the incomplete diesel combustion. Here, we proposed that ceria(CeO2)-based catalysts could lower the temperature at which soot combustion occurred from 610 oC to values included in the operation range of diesel exhausts(270–400 oC). Here, we used the sol-gel method to synthesize catalysts based on mixed oxides(ZnO:CeO2) deposited on cordierite substrates, and modified by ruthenium nanoparticles. The presence of ZnO in these mixed oxides produced defects associated with oxygen vacancies, improving thermal stability, redox potential, sulfur resistance, and oxygen storage. We evaluated the morphological and structural properties of the material by X-ray diffraction(XRD), Brumauer-emmett-teller method(BET), temperature programmed reduction(H2-TPR), scanning electron microscopy(SEM), and transmission electron microscopy(TEM). We investigated how the addition of Ru(0.5 wt.%) affected the catalytic activity of ZnO:CeO2 in terms of soot combustion. Thermogravimetric analysis(TG/DTA) revealed that presence of the catalyst decreased the soot combustion temperature by 250 oC, indicating that the oxygen species arose at low temperatures, which was the main reason for the high reactivity of the oxidation reactions. Comparative analysis of soot emission by diffuse reflectance spectroscopy(DRS) showed that the catalyst containing Ru on the mixed oxide-impregnated cordierite samples efficiently oxidized soot in a diesel stationary motor: soot emission decreased 80%. | L.F.Nascimento R.F.Martins O.A.Serra | 2014 | Journal of Rare Earths2014，32，7： | 6 |
| 6 | Effect of tungsten oxide on ceria nanorods to support copper species as CO oxidation catalysts显示文摘In this work,tungsten oxide with different concentrations(0,0.4 at%,2.0 at%and 3.2 at%)was introduced to the ceria nanorods via a deposition-precipitation(DP)approach,and copper species of ca.10 at%were sequentially anchored onto the modified ceria support by a similar DP route.The aim of the study was to investigate the effect of the amount of tungsten oxide(0,0.4 at%,2.0 at%,and 3.2 at%)modifier on the copper-ceria catalysts for CO oxidation reaction and shed light on the structure-activity relationship.By the aids of multiple characterization techniques including N2 adsorption,high-resolution transmission electron microscopy(HRTEM),powder X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),and temperature-programmed reduction by hydrogen(H2-TPR)in combination with the catalytic performance for CO oxidation reaction,it is found that the copper-ceria samples maintain the crystal structure of the fluorite fcc CeO2 phase with the same nanorod-like morphology with the introduction of tungsten oxide,while the textural properties(the surface area,pore volume and pore size)of ceria support and copper-ceria catalysts are changed,and the oxidation states of copper and tungsten are kept the same as Cu2+and W6+before and after the reaction,but the introduction of tungsten oxide(WO3)significantly changes the metal-support interaction(transfer the CuOx clusters to Cu-[Ox]-Ce species),which delivers to impair the catalytic activity of copper-ceria catalysts for CO oxidation reaction. | Yu'nan Li Lin Gan Rui Si | 2021 | Journal of Rare Earths2021，39，1： | 5 |
| 7 | Modified-EISA synthesis of mesoporous high surface area CeO_2 and catalytic property for CO oxidation显示文摘Mesoporous CeO2 particles with high surface area were synthesized using a modified evaporation-induced self assembly(EISA) method which combined citric acid as complexing agent.As-prepared powder and further thermal treatment samples were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),selected area electron diffraction(SAED),Fourier transform infrared spectrometer(FTIR),thermogravimetry and differential thermal analysis(TG-DTA),Brunauer-Emmett-Teller(BET) and Barrett-Joyner-Halenda(BJH) method.It was found that the cerium oxide/surfactant mixture gave rise to pure and fluorite-structured CeO2 after calcination at 573 K.Moreover,the textural analysis revealed high specific surface area(205 m2/g) and mesoporous structure of the sample.The catalytic performances of mesoporous CeO2 heated at different temperatures for CO oxidation were examined.The catalytic tests exhibited that the product had enhanced catalytic efficiency compared with the decomposed ceria. | 李霞章 陈丰 陆晓旺 倪超英 陈志刚 | 2009 | Journal of Rare Earths2009，27，6： | 5 |
| 8 | A Lamellar Ceria Structure with Encapsulated Platinum Nanoparticles显示文摘A novel lamellar feather-like CeO_(2) structure has been fabricated by using a triblock copolymer as the structure-directing agent.This material was characterized in detail by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,X-ray photoelectron spectroscopy,and BET surface area measurements.Compared with conventional spherical shaped ceria prepared by ammonia gelation,the ceria feathers have superior ability to support nanosized platinum particles due to their special structure.The“skeletons”of ceria feathers can serve as an ideal host matrix to anchor the platinum particles.Furthermore,the inter-crossing pattern of the“skeletons”also acts as a partition to separate platinum particles,allowing the Pt nanoparticles(average diameter~6 nm)to be highly dispersed in the structure.The Pt/feather-like CeO_(2) catalyst exhibits high activity in the water gas shift reaction. | Angelo C.Mak Changlin Yu Jimmy C.Yu Zhendong Zhang Chunman Ho | 2008 | Nano Research2008，1，6： | 5 |
| 9 | Relationship between surface area and crystal size of pure and doped cerium oxides显示文摘Pure and Zr, La or Pr-doped cerium oxides were characterised by transmission electron microscopy (TEM), N2 adsorption-desorption at -196 oC and X-ray diffraction (XRD). For crystal sizes calculation, the Scherrer and Williamson-Hall equations were compared, and the relationship between surface area and crystal size was critically discussed. It was demonstrated that the Williamson-Hall equation must be used instead of the Scherrer equation to calculate crystal sizes, since the latter equation underestimated the crystal size while the former one provided suitable values by taking into account the strain contribution to line broadening. The miscalculation of crystal size by using the Scherrer equation affected both pure and doped cerium oxides, but the size underestimation became more important for high dopant loading. Under the conditions of the BET surface area measurements, N2 molecules were adsorbed on the surface of the single crystals identified by XRD. | C. Bueno-Ferrer S. Parres-Esclapez D. Lozano-Castelló A. Bueno-López | 2010 | Journal of Rare Earths2010，28，5： | 5 |
| 10 | Structure-activity relationship in water-gas shift reaction over gold catalysts supported on Y-doped ceria显示文摘The utilization of pure hydrogen as an energy source in fuel cells gave rise to renewed interest in developing active and stable water-gas shift catalysts. Gold catalysts have proven to be very efficient for water-gas shift reaction at low temperature. The aim of the present study was to investigate the effect of:(i) different preparation methods(impregnation and coprecipitation) to obtain a modified ceria support,and(ii) the amount of Y_2 O_3(1.0 wt%, 2.5 wt%, 5.0 wt% and 7.5 wt%) as dopant on the water-gas shift activity of Au/CeO_2 catalysts. An extended characterization by means of S_(BET), XRD, HRTEM/HAADF, FTIR,H_2-TPR and CO-TPR measurements in combination with careful evaluation of the catalyst behavior allowed to shed light on the parameters governing the water-gas shift activity. The catalysts show very high activity(>90% CO conversion) in the temperature range 180-220 ℃,with a slightly better performance of the gold catalysts on supports prepared by impregnation. The decreased activity with increasing Y_2 O_3 concentration is related to the hindering of oxygen mobility due to ordering of surface oxygen vacancies in vicinity of segregated Y^(3+). The effect of catalyst pre-treatments and the stability of the best performing samples were examined as well. | Tatyana Tabakova Lyuba Ilieva Ivan Ivanov Maela Manzoli Rodolfo Zanella Petya Petrova Zbigniew Kaszkur | 2019 | Journal of Rare Earths2019，37，4： | 4 |
| 11 | Insights on catalytic mechanism of CeO2 as multiple nanozymes显示文摘CeO2 with the reversible Ce3+/Ce4+redox pair exhibits multiple enzyme-like catalytic performance,which has been recognized as a promising nanozyme with potentials for disease diagnosis and treatments.Tailorable surface physicochemical properties of various CeO2 catalysts with controllable sizes,morphologies,and surface states enable a rich surface chemistry for their interactions with various molecules and species,thus delivering a wide variety of catalytic behaviors under different conditions.Despite the significant progress made in developing CeO2-based nanozymes and their explorations for practical applications,their catalytic activity and specificity are still uncompetitive to their counterparts of natural enzymes under physiological environments.With the attempt to provide the insights on the rational design of highly performed CeO2 nanozymes,this review focuses on the recent explorations on the catalytic mechanisms of CeO2 with multiple enzyme-like performance.Given the detailed discussion and proposed perspectives,we hope this review can raise more interest and stimulate more efforts on this multi-disciplinary field. | Yuanyuan Ma Zhimin Tian Wenfang Zhai Yongquan Qu | 2022 | Nano Research2022，15，12： | 4 |
| 12 | Renewable hydrogen production from steam reforming of glycerol(SRG)over ceria-modified Y-alumina supported Ni catalyst显示文摘Excess crude glycerol derived as a by-product from biodiesel industry prompts the need to valorise glycerol to value-added chemicals.In this context,catalytic steam reforming of glycerol(SRG) was proposed as a promising and sustainable alternative for producing renewable hydrogen(H2).Herein,the development of nickel(Ni) supported on ceria-modified mesoporous γ-alumina(γ-Al2 O3) catalysts and their applications in catalytic SRG(at550-750℃ atmospheric pressure and weight hourly space velocity,WHSV,of 44,122 ml·g^-1·h^-1(STP)) is presented.Properties of the developed catalysts were characterised using many technique s.The findings show that ceria modification improved Ni dispersion on γ-Al2 O3 catalyst support with highly active small Ni particles,which led to a remarkable catalytic performance with the total glycerol conversion(ca.99%),glycerol conversion into gaseous products(ca.77%) and H2 yield(ca.62%).The formation rate for H2 production(14.4 ×10^(-5)mol·s^-1·g^-1, TOF(H2)=3412 s^-1) was significantly improved with the Ni@12 Ce-Al2 O3 catalyst,representing nearly a 2-fold increase compared with that of the conventional Ni@AI2 O3 catalyst.In addition,the developed catalyst also exhibited comparatively high stability(for 12 h) and coke resistance ability. | Ammaru Ismaila Huanhao Chen Yan Shao Shaojun Xu Yilai Jiao Xueli Chen Xin Gao Xiaolei Fan | 2020 | Chinese Journal of Chemical Engineering2020，28，9： | 4 |
| 13 | Plasma-electrochemical synthesis of europium doped cerium oxide nanoparticles显示文摘In the present study,a plasma-electrochemical method was demonstrated for the synthesis of europium doped ceria nanoparticles.Ce(NO3)3· 6H2O and Eu(NO3)3·5H2O were used as the starting materials and being dissolved in the distilled water as the electrolyte solution.The plasma-liquid interaction process was in-situ investigated by an optical emission spectroscopy,and the obtained products were characterized by complementary analytical methods.Results showed that crystalline cubic CeO2:Eu3+ nanoparticles were successfully obtained,with a particle size in the range from 30 to 60 nm.The crystal structure didn't change during the calcination at a temperature from 400℃ to 1000℃,with the average erystallite size being estimated to be 52 nm at 1000℃.Eu3+ ions were shown to be effectively and uniformly doped into the CeO2 lattices.As a result,the obtained nanophosphors emit apparent red color under the UV irradiation,which can be easily observed by naked eye.The photoluminescence spectrum further proves the downshift behavior of the obtained products,where characteristic 5Do → 7F1,2,3 transitions of Eu3+ ions had been detected.Due to the simple,flexible and environmental friendly process,this plasma-electrochemical method should have great potential for the synthesis of a series of nanophosphors,especially for bio-application purpose. | Liangliang Lin Xintong Ma Sirui Li Marly Wouters Volker Hessel | 2019 | Frontiers of Chemical Science and Engineering2019，13，3： | 3 |
| 14 | Enhancing low-temperature NO_x storage and reduction performance of a Pt-based lean NO_x trap catalyst显示文摘Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(< 250℃) NO_x storage and reduction performance. The influence of the form of ceria on low-temperature NO_x storage and reduction performance of LNT catalysts was investigated with the focus on NO_x storage capacity, NO_x reduction efficiency during lean/rich cycling, product selectivity and thermal stability.Inductively coupled plasma-atomic emission spectrometry(ICP-AES), Brunner-Emmet-T eller(BET), H_2-pulse chemisorption and X-ray diffraction(XRD) were conducted to characterize the physical properties of LNT catalysts. NO_x storage capacity and NO_x conversion efficiency were measured to evaluate NO_x storage and reduction performance of LNT catalysts. Pt/BaO/CeO_2-Al_2O_3 catalyst exhibits higher NO_x storage capacity than Pt/BaO/CeO_2 + Al_2O_3 catalyst in the temperature range of 150-250 ℃. Meanwhile, Pt/BaO/CeO_2-Al_2O_3 catalyst shows better NO_x conversion efficiency and N_2 selectivity. XRD results indicate that the thermal stability of CeO_2-Al_2O_3 complex oxide is superior to that of pure CeO_2. H_2-pulse chemisorption results show that Pt/BaO/CeO_2-Al_2O_3 catalyst has higher Pt dispersion than Pt/BaO/CeO_2 + Al_2O_3 catalyst over fresh and aged samples. The improved physical properties of Pt/BaO/CeO_2-Al_2O_3 catalyst are attributed to enhance the NOx storage and reduction performance over Pt/BaO/CeO_2 + Al_2O_3 catalyst. | Tong Wang Li-Wei Jia Xiu-Ting Wang Gang Wang Fu-Qiang Luo Jia-Ming Wang | 2019 | Rare Metals2019，38，1： | 3 |
| 15 | 非负载和氧化铝负载的纳米CeO_2-ZrO_2和CeO_2-Te_2O_3固溶体催化CO氧化(英文)显示文摘Ceria-zirconia(CZ)and ceria-terbia(CT)and alumina-supported ceria-zirconia(CZA)and ceria-terbia(CTA)solid solutions were synthesized by coprecipitation and deposition precipitation methods,respectively.Structural characteristics and catalytic activity of the synthesized samples have been investigated using X-ray diffraction(XRD),high resolution transmission electron microscopy(HRTEM),X-ray photoelectron spectroscopy(XPS),Raman spectroscopy(RS),and Brunauer-Emmett-Teller(BET)surface area measurements.To evaluate the catalytic properties,total oxygen storage capacity and CO oxidation activity measurements were carried out.The XRD analyses revealed the formation of Ce0.75Zr0.25O2 phase for CZ and Ce0.5Zr0.5O2 and Ce0.6Zr0.4O2 phases for CZA samples,respectively.While the formation of only Ce0.8Tb0.2O2-δphase was noted for both CT and CTA samples.All the supported and unsupported samples adopted a fluorite-type structure and exhibited cell parameters with respect to Vegard's rule.The HRTEM results indicated well-dispersed particles of the size around 5 nm.The RS measurements suggested the presence of oxygen vacancies due to defective structure formation.The XPS studies revealed the presence of cerium in both Ce 4+ and Ce 3+ oxidation states in different proportions.It was found that CO oxidation for CTA occurs at very much lower temperature than CT,CZ,and CZA samples.Details of these findings by correlating with the structural characterization studies are consolidated. | M.Reddy BENJARAM Thrimurthulu GODE Lakshmi KATTA | 2011 | 催化学报2011，32，5： | 3 |
| 16 | Microwave mediated synthesis and characterization of CeO_2-GO hybrid composite for removal of chromium ions and its antibacterial efficiency显示文摘A facile fabrication and processing of cerium oxide-graphene oxide(CeO_2-GO) hybrid nanocomposites without the use of any surfactant or any organic solvents using chemical method and treatment with microwave irradiation technique are reported. In-situ hexagonal nano cerium oxide particles embedded on the layered surface of GO sheets were investigated for the photodegradation of dyes, removal of chromium Cr(VI) ions and against antibacterial studies. The results imply that hybrid nanocomposites shows enhanced 5-folds of photocatalytic activities in UV(ultraviolet) light irradiation and exhibited rapid efficiency in the elimination of chromium ion better than the pure GO and CeO_2, which are inhibited by competent photosensitive electron inoculation and controlling the electron–hole recombination. The synergetic effect of CeO_2-GO composites played a vital role in showing better results against model bacterium than GO and CeO_2 are due to higher physical interaction endorsed to the stress of membranes acute by piercing edges,large surface area, and higher adsorptive conditions of graphene oxide sheets tailored with ceria particles. The amount of charge transferred at the interface increases with the concentration of O atoms, demonstrating the interaction between CeO_2 and GO is much stronger than CeO_2 and GO are due to the decrease of the average equilibrium distance between the interfaces. The CeO_2-GO interface staggered band alignments existing between the CeO_2 surfaces and GO which shows an excellent synergism. The structure and morphology of composites were tested by X-ray diffraction(XRD), Fourier transform infrared(FTIR), Raman, X-ray photoelectron spectroscopy(XPS), and high-resolution transmission electron microscope(HR-TEM). | Lellala Kashinath Keerthiraj Namratha Kullaiah Byrappa | 2019 | Journal of Environmental Sciences2019，31，2： | 3 |
| 17 | Effective removal of automobile exhausts over flower-like Ce_(1-x)Cu_xO_2 nanocatalysts exposed active {100} plane显示文摘This work elucidates the synthesis and characterization of copper ions incorporated ceria(Ce_(1-x)Cu_xO_2)nanocatalysts with 3 D flower-like and nanocrystalline morphology for the purification of automobile exhausts. XRD and Raman results confirm the presence of copper ions in ceria. The 3 D flower-like and nanocrystalline morphology exhibited by these catalysts were seen by FESEM images. HRTEM and SAED results confirm that(100) plane is dominantly presented in 3 D flower-like Ce_(1-x)Cu_xO_2 catalysts when compared to nanocrystalline morphology. The textural properties of synthesized catalysts was done with the help of N2 sorption study, which confirms that flower-like Ce_(1-x)Cu_xO_2 catalysts show high surface area and pore volume. The existence of Ce^(3+), Ce^(4+), Cu^+ and Cu^(2+) ions in the catalyst were examined by XPS and DR UV-Vis techniques. Oxygen storage capacity(OSC) of the catalysts was studied by H_2-TPR analysis. These characterization results elucidate the presence of dominant active sites(Ce^(3+), Ce^(4+), Cu^+and Cu^(2+)) and {100} plane in the flower-like morphology compared to nanocrystalline. The catalytic activity of synthesized Ce_(1-x)Cu_xO_2 catalysts was tested for removal of CO, HC_x and NO gases from automobile emission with respect to the copper content and morphology. The obtained results indicate that the presence of optimum amount of copper in ceria with flower-like morphology is essential for the removal of CO, HC_x and NO at low temperature via redox process, which is due to the presence of active sites on the dominant {100} plane. | A.Selvamani K.Shanthi D.Santhanaraj C.M.Babu V.V.Srinivasan P.Thirukumaran V.Ramkumar A.Shakilaparveen R.Balasubramanian | 2018 | Journal of Rare Earths2018，36，6： | 3 |
| 18 | Solar chemical looping reforming of methane combined with isothermal H2O/CO2 splitting using ceria oxygen carrier for syngas production显示文摘The chemical looping reforming of methane through the nonstoichiometric ceria redox cycle(CeO2/CeO2-δ) has been experimentally investigated in a directly irradiated solar reactor to convert both solar energy and methane to syngas in the temperature range 900–1050 °C. Experiments were carried out with different ceria shapes via two-step redox cycling composed of endothermic partial reduction of ceria with methane and complete exothermic re-oxidation of reduced ceria with H2 O/CO2 at the same operating temperature, thereby demonstrating the capability to operate the cycle isothermally. A parametric study considering different ceria macrostructure variants(ceria packed powder, ceria packed powder mixed with inert Al2 O3 particles, and ceria reticulated porous foam) and operating parameters(methane flow-rate, reduction temperature, or sintering temperature) was conducted in order to unravel their impact on the bed-averaged oxygen non-stoichiometry(δ), syngas yield, methane conversion, and solar reactor performance. The ceria cycling stability was also experimentally investigated to demonstrate repeatable syngas production by alternating the flow between CH4 and H2 O(or CO2). A decrease in sintering temperature of the ceria foam was beneficial for increasing syngas selectivity, methane conversion,and reactor performance. Increasing both CH4 concentration and reduction temperature enhanced δ with the maximum value up to 0.41 but concomitantly favored CH4 cracking reaction. The ceria reticulated porous foam showed better performance in terms of effective heat transfer, due to volumetric absorption of concentrated solar radiation and uniform heating with lower solar power consumption, thereby promoting the solar-to-fuel energy conversion efficiency that reached up to 5.60%. The energy upgrade factor achieved during cycle was up to 1.19. Stable patterns in the δ and syngas yield for consecutive cycles with the ceria foam validated material performance stability. | Srirat Chuayboon Stéphane Abanades Sylvain Rodat | 2020 | Journal of Energy Chemistry2020，29，2： | 2 |
| 19 | Effects of reduction temperature and content of Pd loading on the performance Pd/CeO2 catalyst for CO oxidation显示文摘The content of noble metal loading and the reduction process of the catalysts are important factors influence the economic indicator and catalytic performance for industrial catalysis. In the present work, Pd/CeO2NT (Pd supported on the CeO2 nanotubes) catalysts are prepared with the hydrothermal synthesized CeO2NT and glutathione (GSH) reduced Pd nanoparticles via impregnation. The content of Pd loading as well as the catalysts reduction temperature are optimized to the CO oxidation reduction. Our results show that the best Pd loading is 1.5%Pd/CeO2NT. The catalysts reduced at 350 ℃ for 2 h prior to catalytic reaction perform the best toward CO oxidation, which reaches completely CO conversion at 70 ℃. The XRD, Raman, H2-TPR, TEM, BET and XPS characterization reveal that the excellent catalytic performance of 350 °C 1.5%Pd/CeO2NT sample can be attributed the high Pd^0 species and oxygen vacancy in the sample, which are important factors influence the activity of the catalysts. | Yue Yan Huaxi Li Zhanghui Lu Xuewen Wang Rongbin Zhang Gang Feng | 2019 | Chinese Chemical Letters2019，30，6： | 2 |
| 20 | Construction of mesoporous ceria-supported gold catalysts with rich oxygen vacancies for efficient CO oxidation显示文摘Bearing unique redox nature and high oxygen storage capacity,ceria(CeO_(2))has always been a promising CO oxidation catalyst support for gold(Au)catalysts and the like.Herein,a series of Au-CeO_(2)-P(P stands for pH value)samples was prepared by a co-precipitation method with the assistance of an alkaline environment and amino groups functionalized ordered mesoporous polymer(OMP-NH_(2)).Afterward,all samples described above were characterized that the Au-CeO_(2)-P catalysts are made of Au-Ce-O solid solution and Au nanoparticles(NPs)supported on CeO_(2).It turns out that OMP-NH_(2) is not just a simple sacrificial template for mesoporous structure,but also plays an important role as an amino source,explaining the presence of rich oxygen vacancies.Due to the concentration of oxygen vacancies in Au-Ce-O solid solution is the key factor for the oxygen mobility of CO oxidation,the catalytic results also demonstrate that the catalytic activity of Au-CeO_(2)-P catalysts is related to the concentration of their oxygen vacancies.Moreover,Au-CeO_(2)-9.6 with a highest concentration of oxygen vacancies(as high as 13.98%)in Au-CeO_(2)-P catalysts exhibits the best catalytic activity(complete conversion at 10℃). | Xin Shen Wang Li Shunmin Ding Xiaohua Ma Shaohua Wu Weiming Xiao Rong Zeng Sanguo Hong Chao Chen | 2022 | Journal of Rare Earths2022，40，3： | 2 |
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