JOURNAL OF NUCLEAR MATERIALS
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2017
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IF 2.048
Yi Ding,Xinggui Long,Shuming Peng,Dong Zhang,Zhaoyi Tan,Xirui Lu
Zr 1− x − y Ce x Nd y O 2− y/ 2 ceramics, which were designed as waste form materials, were obtained by simultaneous substitution of Ce 4+ and Nd 3+ for Zr 4+ in ZrO 2 . The influences of the simultaneous substitution of Ce and Nd on phase transformation of ZrO 2 were investigated systematically. Also, the aqueous durability of the ceramics was evaluated. The results show that the phase transformation caused by the simultaneous substitution mainly relates to the total content of Ce and Nd. The ZrO 2 ceramics containing Ce + Nd < 30 mol% exhibit both monoclinic and cubic phases, while the ceramics containing Ce + Nd ≥ 30 mol% are cubic phase. And the cubic phase can be stabilized by incorporating 30 mol% Ce + Nd. Moreover, LR i are modified by the incorporation of Ce and Nd, because of the presence of oxygen vacancies . The Nd and Ce co-doped zirconia waste form exhibit excellent aqueous durability (∼10 −5 g m −2 d −1 ).
研究领域:
材料科学
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核废料管理
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陶瓷工程
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Pengchao Ren,Weifeng Tu,Chanchan Wang,Sifan Cheng,Wenqi Liu,Zhenzhou Zhang,Yun Tian,Yi-Fan Han
This study investigated the Cu-CeO 2 interactions for CO hydrogenation to methanol by applying rate measurements, chemical titration/desorption, together with in-situ/operando spectroscopy techniques under realistic reaction conditions. Ce components were enriched in the surface region of Cu/CeO 2 catalysts while Ce 3+ and Ce 4+ atoms co-existed during CO hydrogenation. The ratio of Ce 3+ to Cu 0 in the surface region of catalysts increased linearly with the Ce content. The turnover rates of CH 3 OH formation increased as a single-valued function of the ratio, irrespective to the individual contact extent between Cu and CeO 2 clusters or Ce content in the Cu/CeO 2 catalysts, indicating that the Cu 0 -Ce 3+ sites pair acts as active sites for CO hydrogenation to methanol over Ce-CeO 2 samples. This study also unraveled that formyl and formate species, as reactive surface intermediates, were co-adsorbed on the Cu 0 -Ce 3+ sites, and their hydrogenation routes occurred concurrently for CH 3 OH formation during CO-H 2 reactions.
研究领域:
催化
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化学工程
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表面科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
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IF 4.758
Rui Liu,Ran Yang,Chaojie Qu,Haichen Mao,Yue Hu,Jianjun Li,Lingbo Qu
In this work, highly photoluminescent glycine (GLY) functionalized graphene quantum dots (GQDs) (GLY-GQDs) were synthesized by a simple and green pyrolysis method employing ethylene glycol as carbon source, GLY as functional molecule. The as-synthesized GLY-GQDs exhibited excellent water solubility with a fluorescence quantum yield of 21.7%. The fluorescence of GLY-GQDs was intensively quenched by Ce 4+ via forming non luminescent complexes of GLY-GQDs-Ce 4+ . When ascorbic acid (AA) was in presence, Ce 4+ was reduced to Ce 3+ and the fluorescence of GLY-GQDs regained. In the light of this theory, a simple AA sensor was fabricated without complicated, costly and time-consuming operations. Under the optimal conditions, the fluorescence recovery ratio and the concentration of AA has a linear relationship in the range of 0.03–17.0 μM and with a detection limit of 25 nM which was one order higher sensitive than the reported methods Furthermore, this established sensor system also shows a high selectivity toward AA over a wide range of common biological molecules such as uric acid, dopamine and glutathione and so on. The proposed method was successfully applied for the AA detection in serum samples. All these suggested the potential of this GLY-GQDs based sensor in the clinical analysis.
研究领域:
材料科学
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分析化学
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生物化学
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纳米技术
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DOI
高影响因子
Environmental Progress & Sustainable Energy
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2016
·Vol. 36
·期 2
·494-504
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IF 1.631
Zhengjiang Liu,Lei Xing,Huiyan Ma,Lin Cheng,Juming Liu,Jucai Yang,Qiancheng Zhang
Sulfated Ce-doped TiO 2 photocatalysts, with improved visible light photocatalytic activity, are prepared by sol-gel method and via impregnation with diluted sulfuric acid. The synthesized samples are characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet–visible diffuse reflectance spectra (UV–Vis DRS), Fourier transform infrared (FTIR) spectroscopy, temperature-programmed desorption of ammonia (NH 3 -TPD) and X-ray photoelectron spectroscopy (XPS). To investigate the effect of Ce doping as well as acid sites on the photoactivity of the synthesized photocatalyst, photocatalytic degradation of Rhodamine B in an aqueous solution is used as a probe reaction to evaluate the photocatalytic activity of the as-prepared samples under visible light irradiation. It reveals that Ce doping can improve the photocatalytic response of TiO 2 to visible light and the presence of Ce 4+ /Ce 3+ redox process facilitates the separation of photo-generated electrons and holes. In addition, the impregnation can create Lewis acid sites on the obtained catalyst surface. Lewis acid sites on the catalyst surface could increase the amount of adsorbed oxygen (O ad ) and consequently improve the transform efficiency of Ce 3+ to Ce 4+ . Thereafter an increase in the phtocatalytic activity of sulfated Ce-doped TiO 2 is achieved. The possible mechanism of RhB degradation by sulfated Ce-doped TiO 2 photocatalyst is preliminarily discussed. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 494–504, 2017
研究领域:
环境工程
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材料科学
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化学工程
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Zhi Zhu,Changchang Ma,Kesheng Yu,Ziyang Lu,Zhi Liu,Pengwei Huo,Xu Tang,Yongsheng Yan
In the present study, we constructed the Ce-doped biomass carbon-based mesoporous g-C 3 N 4 photocatalyst via alternanthera philoxeroides griseb growing guide using calcination method. The Ce-C@g-C 3 N 4 exhibited more superior photocatalytic performance for 2-mercaptobenzothiazole (96 %) degrading than that of pure g-C 3 N 4 (39 %) and C@g-C 3 N 4 (60 %). As a consequence, the improved degradation efficiency of Ce-C@g-C 3 N 4 attributed to the biomass carbon can significantly enhance the mass transport channels of electron-hole pairs. Meanwhile, the doped Ce 4+ ions acting as the redox center can sufficiently utilize the photogenerated carriers for generating more active radicals. Also, the possible photocatalytic reaction mechanisms including transfer behaviors of charge carriers, generation of reactive species, intermediate degradation products are also discussed in detail. This work may provide a promising approach for synthesizing g-C 3 N 4 -based photocatalyst by the plant growing guide and application in wastewater treatment.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
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