共查询到16条相似文献,搜索用时 93 毫秒
1.
Bing Zhou Quanli Ke Meijun Wen Tianbiao Ying Guokai Cui Ying Zhou Zhenyu Gu Hanfeng Lu 《中国稀土学报(英文版)》2023,41(8):1171-1178
CeO2,La2O3,and CeO2-Y2O3 oxides were coated on the surface of spherical granular AI2O3(3-5 mm)through impregnation method,and proved as better supports of Pd and Pt catalysts.The influences of rare earth metal doping on the adsorption rates of Pd and Pt ions,as well as the catalytic performance,were investigated.Results show that the H2PtCl6·6H2O adsorption rates of the Al 相似文献
2.
Developing high-performance ammonia decomposition catalysts for preparing COx-free hydrogen shows great practical significance.Herein,CeO2 is used as a promoter to modulate the metal-support interaction to enhance the catalytic performance of Ru/Al2O3 catalysts.A series of 1Ru/xCe-10AI(x=0.5,1,or 3)catalysts was prepared by a facile colloidal deposition method.We find that the optimized 1 Ru/1Ce-10Al catalyst exhibits excellent activity for the decompo... 相似文献
3.
Xia Gong Quanquan Shi Xinyu Zhang Jinmei Li Guichen Ping Hui Xu Hongjing Ding Gao Li 《中国稀土学报(英文版)》2023,41(2):233-239
Selective hydrogenation of unsaturated aldehydes remains a grand challenge in controlling chemoselectivity up to now.We synthesized a series of PtFex/CeO2 catalysts,which were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS) as well as temperature-programmed-reduction by hydrogen(H2-TPR).The catalytic performance of PtFex/CeO2,including cinnamaldehyde(CAL) conversion and sele... 相似文献
4.
In this paper,a hydrothermal method was used to prepare(Ce,Cr)-MOF with different Ce/Cr molar ratios and then a series of CeO2-Cr2O3 mixed metal oxides(CeCr-MMO) with mesoporous structure were prepared by thermal decomposition of these MOFs at different temperatures.After a series of characterization techniques were applied to test the physicochemical properties of the materials,it is found that thermal decomposition temperature(TDT) and Ce/Cr molar ratios have i... 相似文献
5.
Jie Deng Shanshan Li Xinyi Yin Mengchen Li Jianli Wang Yongdong Chen Yaoqiang Chen 《中国稀土学报(英文版)》2023,41(1):67-76
Ceria-zirconia based(CZ) materials are still a crucial component of three-way catalysts(TWCs) now.Compared with traditional cubic or tetragonal phase,CZ material with pyrochlore-type κ-Ce2Zr2O8 phase shows an excellent oxygen storage capacity,and thus is examined as a promising material for developing TWCs.Considering the remarkable surface Ce/Zr ratio change during the κ-Ce2Zr2O8 formation,we investigated the effects of surface C... 相似文献
6.
Luyao Zhang Fuli Tian Huan Li Jiangman Meng Qi Liu Xiaoqian Guo Yun Qiu Jun Zhang Changyan Li 《中国稀土学报(英文版)》2023,41(9):1437-1447
A series of non-enzymatic graphene functionalized biosensors was developed via deposition precipitation method for lactic acid(LA) detection,which we re characterized by transmission electron micro scopy(TEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),gas chromatography-mass spectrometry,liquid chromatography-mass spectro metry,and proton nuclear magnetic re sonance(1H NMR).The electrochemical performances of the non-enzymatic biosensors were measured by means of the ele... 相似文献
7.
Cerium oxide(CeO2) coated on copper modified attapulgite clay nanocomoposite(CeO2/Cu2+-ATP) was prepared by homogeneous deposition method.The microstructures of the as-prepared CeO2/Cu2+-ATP nanocomposites were characterized by X-ray diffraction(XRD),energy-dispersive spectrometer(EDS) and transmission electron microscopy(TEM).The results indicated that CeO2 particles with average size of about 5 nm were loaded onto the Cu2+-ATP and were widely dispersed.Comparing the catalytic activity of ATP/CeO2 and CeO2/Cu2+-ATP,the catalytic activity was improved when a small quantity of Cu2+ was introduced.The loading amount of CeO2 and reaction temperature had important effects on decolorization ratio of methyl orange(MO).When the loading amount and reaction temperature were 70% and 338 K,respectively,the decolorization ratio of MO reached over 99%,which showed excellent catalytic activity. 相似文献
8.
The 7 wt% rare earth metal oxide promoted Ni-SiO2 catalysts of Ni-7Pr6O11-SiO2,Ni-7Nd2O3-SiO2,and Ni-7Sm2O3-SiO2 were prepared by the complex-decomposition method,and were comparatively evaluated for pressurized carbon dioxide reforming of methane(CRM) under severe conditions of 750℃,1.0 MPa,CH4/CO2=1,and gas hourly space velocity of 53200 mL/(g·h).The addition of r... 相似文献
9.
Ce3+as the active site on the CeO2 abrasive surface is the key to enhancing the material removal rate(MRR).The CeO2 abrasives with high chemical activity were prepared by the molten salt method under a reducing atmosphere.The crystal structure and morphology of CeO2 abrasive s were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR),ultraviolet—vi... 相似文献
10.
Sm and Ho were doped in Ce-Mn/TiO2 catalyst respectively to enhance its denitration performance at low temperature.X-ray diffraction(XRD),N2 adsorption-desorption,X-ray photoelectron spectroscopy(XPS),NH3-temperature programmed desorption(NH3-TPD),H2-temperature programmed reduction(H2-TPR) and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) techniques were used to analyze the structure and performance ... 相似文献
11.
《中国稀土学报(英文版)》2022,40(5):737-744
As the oxygen redox ability shows great effects on the catalytic performances of ceria-zirconia based materials, many strategies have been utilized to improve the oxygen storage capacity. Here in this study, we report a simple and facile approach to prepare a SO42–-modified La, Y-doped ceria-zirconia material (SO/CZLY-f) with high oxygen storage capacity. Due to the additional redox process between SO42? and S2?, oxygen storage capacity of SO/CZLY-f (745.3 μmol O2/g) is about 1.6 times higher than that of La, Y-doped ceria-zirconia material without SO42– modification. Moreover, the catalytic activities and stability of the corresponding Pd-only three-way catalyst were measured. Compared to that of Pd@CZLY-f, the operation window of CO, full conversion temperature of HC and NO over Pd@SO/CZLY-f are obviously widened and lowered, respectively. After aging treatment at 1100 °C for 4 h, the superiority of aged Pd-loading composite is still maintained. 相似文献
12.
Ying Xin Hanxue Zhang Pan Li Ningning Qu Ahui Tang Fuzhen Yang Dongxu Han Junxiu Jia Jin Wang Lirong Zheng Zhaoliang Zhang 《中国稀土学报(英文版)》2023,41(6):905-916
The next-generation Euro 7 standard proposed much lower pollutant limits from gasoline vehicles,specifically for CO and NOx,which would be challenging for the three-way catalysts(TWCs) utilized commercially to eliminate these pollutants.TWCs with reductive(Rh) and oxidative(Pd) active components on gasoline particulate filters(TWC on GPF) play importantly auxiliary roles in the remediation of CO and NOx downstream the close coupled TWCs to meet their emission targets.Here,a... 相似文献
13.
《中国稀土学报(英文版)》2022,40(11):1743-1750
The plane exposure of support vitally affects the catalytic performance of the catalyst. In this work, CeO2 nanorods ((110) plane exposure), nano-octahedrons ((111) plane exposure) and nano-cubes ((100) plane exposure) were prepared as the supports of Pt/CeO2 samples to investigate the effect of CeO2 plane exposure on total toluene oxidation. Characterizations reveal that the (110) plane of CeO2 is more helpful to the dispersion of Pt species, followed by (111) face. The improved dispersion of Pt species can enhance the metal-supports interaction, which promotes the electron transfer of CeO2 carrier to Pt nanoparticles and the adsorption-activation of O2, thereby facilitating the total oxidation of toluene via the Langmuir–Hinshelwood (L-H) mechanism. Therefore, Pt/CeO2-r (nanorods) sample expresses excellent catalytic performance of toluene oxidation. Finally, the procedure of toluene total oxidation was studied by in-situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. We expect that this work can contribute to the development of an effective sample for the decomposition of volatile organic compounds (VOCs). 相似文献
14.
Jiaxuan Li Xiangyang He Wei Xiong Li Wang Baoquan Li Jin Li Shujuan Zhou Huizhong Yan 《中国稀土学报(英文版)》2023,41(2):268-276
The effects of different proportions of La and Y elements in the A-side on the structure and properties of A2B7-type La-Y-Ni hydrogen storage alloys were investigated.The(La,Y)2Ni7 hydrogen storage alloys with different La/Y ratios were prepared by sintering the Y2Ni4 precursor and different AB5-type precursors at 1298 K for 5 h and subsequently annealed for 20 h at 1248 K.All the alloys only contain Ce2Ni 相似文献
15.
《中国稀土学报(英文版)》2020,38(8):883-890
A series of supported CeO_2/TiO_2 catalysts were prepared to explore the influence of CeO_2 loading on these catalysts for the selective catalytic reduction of NO_3 by NH_3(NH_3-SCR).The catalysts were investigated in detail by means of XRD,Raman,H_2-TPR,NH_3-TPD,XPS,in situ DRIFTS,and NH3-SCR reaction.The activity of the catalyst is closely related to the content of CeO_2.When the loading of CeO_2 is near the dispersion capacity(1.16 mmol Ce~(4+)/100 m~2 TiO_2),the catalytic activity is better.This may be because that the dispersed CeO_2 is the active species and the catalyst has appropriate redox property,along with the larger amounts of surface Ce content and surface adsorbed oxygen species.Finally,a possible reaction mechanism via the Langmuir-Hinshelwood(L-H) mechanism is tentatively proposed to further understand the NH_3-SCR reaction. 相似文献
16.
《中国稀土学报(英文版)》2020,38(12):1372-1378
In this study, hierarchical Ag/La2O2CO3 micro/nanostructures (MNSs) were synthesized by in situ loading Ag nanoparticles (NPs) on the surface of the La2O2CO3 MNSs. The prepared La2O2CO3 MNSs present flower-like shape and can be tuned by the molar ratio of La (NO3)3 and CO(NH2)2. In the molar ratio of 1:2 to 1:55, the La2O2CO3 MNSs mainly consist of polyhedral rods, irregular rods and irregular spindles and their size is about 10, 8 and 7 μm, respectively. After loading Ag NPs, the spindle-like Ag/La2O2CO3 MNSs were used for phosphate removal and antibacterial activity. At the initial phosphate concentration of 20 mg/L, the removal rate is 59.6%. The Ag/La2O2CO3 MNSs have significant antibacterial activity and their MIC values for S. aureus and E. coli are 31.3 and 15.6 μg/mL, respectively. The results indicate that Ag/La2O2CO3 MNSs may have good application prospects in open water to inhibit bacterial growth. 相似文献