SURFACE & COATINGS TECHNOLOGY
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2017
·
IF 2.589
Xue-Ling Wei,Na Li,Wen Jun Yi,Li-Jun Li,Zi-Sheng Chao
The super-hydrophobic (SH) porous ceramics material with good stability was successfully prepared via the hydrothermal growth of CeO 2 micro/nano-structure and the subsequent dip-coating of low surface energy substance 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) over the surfaces of ZrO 2 -SiO 2 porous ceramics substrate. The surface morphology , chemical composition and wettability of material were investigated by means of SEM, EDS, XRD , FT-IR, and contact angle measurement. It was found that a layer of CeO 2 nano-flowers had been attached over the surfaces of ZrO 2 -SiO 2 porous ceramics substrate, using the optimized concentration of CeNO3 precursor, and after the grafting of PFDTES, the super hydrophobicity of the obtained material was achieved, with the water contact angle being as high as 162° and sliding angle being approximately 0°. Particularly, the super hydrophobicity was found to occur also in the pores of the obtained material. The obtained material was found to possess the significantly large thermal and chemical stabilities.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2022
·
IF 9.221
Shuang Li,Yuchi Zhang,Le Han,Xianliang Li,Yan Xu
Heterojunction formation has been considered as an effective way for exploring ultrahigh sensitive multi-metal oxide based gas sensors. Herein, unique hierarchical radial CeO 2 /ZnO heterostructures with excellent triethylamine (TEA) gas-sensing performance were successfully prepared via a feasible solvothermal method . The morphology, microstructure and gas-sensing performance of the composite were systematically characterized and investigated. The selective TEA gas response of the radial CeO 2 /ZnO heterostructure was increased by ten times as compared to that of pure ZnO phase, ascribing to the abundant reactive sites induced by the formation of n-n heterojunction . Furthermore, the radial CeO 2 /ZnO n-n heterojunction exhibited the best TEA gas sensitivity with R a /R g = 92.17 at an operating temperature of 200 °C, a fast response/recovery time of 29 s/23 s, and a long-term stable repeatability for at least 60 days. The excellent selectivity of CeO 2 /ZnO heterojunction for TEA sensing is also remained even when mixing with other interferent gases. The interface-dependent and enhanced TEA sensing property of CeO 2 /ZnO can be ascribed to its intriguing radial morphology, for which the CeO 2 nanoparticles located in the internal structure of the composite while the ZnO hexagonal prism grew radially outward. The well assembled hierarchical CeO 2 /ZnO n-n heterojunction with abundant accessible active sites significantly facilitate the surface reaction and diffusion of target gas molecules at the interface between CeO 2 and ZnO during gas sensing process.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Xiaodong Hao,Tingting Wei,Qiheng Ma,Yuhao Zhou,Yang Yang,Yunxiang Jing,Xinyi Feng,Xishuo Zhang,Jin Zhang,Deqiang Yin,Zhen-Hong He,Shufang Ma,Bingshe Xu
The advancement of cost-effective and highly efficient electrocatalysts for hydrogen evolution is pivotal in fostering the progress of clean energy technologies. In this study, we present a reforming approach aimed at facile fabrication of the Cr-CeO2/rGO electrocatalyst. This involves incorporating a limited quantity of reduced graphene oxide (rGO) to serve as a conductive scaffold for CeO2 nanocrystals (NCs) while also introducing Cr, a transition metal, as an active dopant. It is found that the introduction of Cr and rGO induces charge transfer, leading to enhanced electrical conductivity and the creation of additional active sites on the nanocomposite surface. The synergy between rGO and CeO2, along with Cr doping in CeO2, significantly improves HER performance. The representative sample of the Cr(5%)-CeO2/rGO catalyst demonstrates a low overpotential of 83 mV at a current density of 10 mA cm–2, a low Tafel slope of 81 mV dec–1, and excellent stability under alkaline conditions. Significantly, this value of overpotential is reduced by 81 and 127 mV compared to those of the CeO2/rGO nanocomposites and the pristine CeO2 NCs. Theoretical density functional theory calculations additionally validate the phenomenon of charge transfer and improved HER properties, with Cr-CeO2 displaying a favorable Gibbs free energy (ΔGH*) for H* adsorption. This study offers novel insights into the design of precious metal electrocatalysts featuring functional interfaces and a wealth of active sites, holding great promise for industrial applications in clean energy conversion and storage.
研究领域:
材料科学
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能源技术
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ADSORPTION SCIENCE & TECHNOLOGY
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2017
·
IF 0.754
Jin Lin,Yan Wu,Afshin Khayambashi,Xiaolong Wang,Yuezhou Wei
The silica-based CeO2 adsorbent (CeO2/SiO2) was prepared for removing fluoride from the aqueous solution. The synthesized adsorbent was characterized by scanning electron microscope, energy dispersive spectrum, X-ray diffractometer, Fourier transform infrared spectrometer, and zeta potential measurement analyses. The adsorption batch experiments in the various experimental conditions including solution pH, contact time, initial fluoride concentration, and adsorption temperature were performed and investigated. The maximum adsorption capacity of fluoride into CeO2/SiO2 was 2.441 mmol/g at pH 3 and 298 K. The adsorption kinetics and isotherms were well described by the pseudo-second-order model and the Langmuir model, respectively. The fluoride adsorption reached the equilibrium in 15 min from the aqueous solution with the initial fluoride concentration of 400 mg/l at 298 K. In the temperature range of 298–338 K, the maximum adsorption capacity of fluoride decreased from 2.441 mmol/g to 2.109 mmol/l at pH 3. The adsorption thermodynamics study revealed that this process was a spontaneous, exothermic, and entropy-driving adsorption. Furthermore, the mechanism of adsorption was identified as the anion exchange and the electrostatic interaction. The desorption efficiency of fluoride-loaded CeO2/SiO2 adsorbent could reach about 95% by 0.1 mol/l NaOH.
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
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Lili Zhang,Yuanting Lei,Wenjing Xu,Dan Wang,Yafei Zhao,Wenxing Chen,Xu Xiang,Xinchang Pang,Bing Zhang,Huishan Shang
Developing high-efficiency, low-cost, and durable bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is greatly desirable and challenging. Herein, a highly active and durable nitrogen-doped CoP coupled CeO 2 nanowire heterostructure ( N -CoP/CeO 2 ) electrocatalyst is prepared on carbon cloth. The resultant N -CoP/CeO 2 exhibits superb catalytic activities for OER and HER, featuring low overpotentials of 215 and 74 mV at 10 mA cm −2 in 1.0 M KOH. The N -CoP/CeO 2 assembled water electrolyzer has super stability, which needs relatively low cell voltages of 1.52 V@10 mA cm −2 over 42 days (≈95.9 % retention) and 1.80 V@400 mA cm −2 over 21 days (≈94.4 % retention), outperforming most reported cost-effective electrocatalysts. Theoretical calculations reveal that the metallic heterostructure interfaces of N -CoP/CeO 2 possess a fast electron transfer pathway, optimized adsorption/desorption process of reactive intermediates, and reduced reaction energetic barriers, thus enhancing the electrocatalytic activity. Additionally, the robust three-dimensional configuration and the oxygen vacancies-rich CeO 2 component in N -CoP/CeO 2 are regarded as significant contributors to improving stability and promoting long-term durability.
研究领域:
材料科学
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电化学
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能源催化
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
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2016
·Vol. 6
·期 19
·7273-7279
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IF 5.287
Guozhu Chen,Qihui Xu,Yong Wang,Guolong Song,Cuncheng Li,Wei Zhao,Weiliu Fan
It is still an important issue to develop a facile, environmentally friendly way to synthesize bimetal oxide materials. In this paper, Co3O4–CeO2 core–shell catalysts were prepared by an interfacial reaction, where Co(CO3)0.35Cl0.2(OH)1.1 nanorods were dispersed in Ce3+ aqueous solution for 2 days, followed by a calcination step. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Based on the characterization and comparative experimental results, we proposed that the OH− ions slowly dissociated from the Co(CO3)0.35Cl0.2(OH)1.1 precursor combined with Ce3+ to develop into Ce(OH)3 nanoparticles because of its smaller solubility product constant than that of the Co precursor or Co(OH)2. Neither an additional precipitation agent nor stabilizing molecules were employed during the whole preparation. Raman spectroscopy and H2-temperature programmed reduction (H2-TPR) analysis revealed that there is a synergistic effect between Co3O4 and CeO2 in the as-prepared Co3O4–CeO2 core–shell catalysts, which is responsible for their enhanced catalytic activity toward CO oxidation in comparison to pure Co3O4 and CeO2.
研究领域:
催化材料
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
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2020
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IF 2.029
Jian Pan,Junchao Qian,Zhengying Wu,Chengbao Liu,Yiyang Liu,Yucheng Qian
The increasing demand for power storage device with high energy density forces the scientists to design new materials as electrodes. In this work, hollyhock stalks were converted into porous carbon host for growth of MnO and CeO 2 nanocrystals hydrothermally. The obtained biocarbon with macro-meso-micro porous structure provides excellent electron transport properties, while the nano-size MnO-CeO2 (<10 nm) on it grants high capacitance. Due to the unique nanostructure of carbon skeleton and ultra-large surface areas (514.4 m 2 g −1 ), the MnO-CeO 2 nanocrystals/porous carbon displays excellent electrochemical capacitance performance (162 F·g −1 at 0.5 A·g −1 ) and cycle stability. The specific capacity remains 99.3% efficiency after 1000 cycles at 500 mA·g −1 .
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Arabian Journal of Chemistry
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2020
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IF 4.762
Kechen Song,Shuo Wang,Qiang Sun,Deping Xu
Nano-sheets Al 2 O 3 supported CeO 2 -Fe 2 O 3 binary oxides were prepared by the vacuum impregnation method. The structural and textural properties were characterized by pertinent techniques, and the materials were evaluated as catalysts for the oxidative dehydrogenation of ethylbenzene with carbon dioxide (CO 2 -ODEB). The characterization results show that all samples maintain the hierarchical structure, and CeO 2 -like and Fe 2 O 3 -like solid solutions were formed when changing the Ce-to-Fe molar ratio. The catalytic performances indicate that CeO 2 -Fe 2 O 3 binary oxides were effective for CO 2 -ODEB, and the activity is determined by mobile oxygen, which can facilitate the dehydrogenation process. The DFT studies further identified the reaction pathway and rate-determining step. The inter-transmission of oxygen species and the presence of CO 2 refill the oxygen vacancies and restore the redox cycle of CeO 2 -Fe 2 O 3 binary oxides.
研究领域:
催化化学
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材料科学
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理论计算化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2016
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IF 3.205
Yushan Hou,Jianfang Wu,Elena Yu. Konysheva
Quantitative analysis of Cr-adsorption from a gas phase on CeO 2 , pure and doped BaCeO 3 was performed in combination with surface techniques and electrochemical impedance spectroscopy . The Cr-adsorption on BaCeO 3 is 3 times higher than on CeO 2 and it increases by 12–25% on In doping in Ba(Ce 1−x In x )O 3 (x = 0.1–0.3) in the temperature range of 600–700 °C. These perovskites adsorb chromium with the formation of a multi-phase surface layer containing BaCr 6+ O 4 and cerium oxide. Coexistence of small fractions of Cr 3+ and Cr 5+ cations in the surface layer was identified by X-ray photoelectron spectroscopy. The thickness of the surface layer and its morphology vary with temperature, affecting the conductivity of Ce containing perovskites below 700 °C. BaCrO 4 exhibits under air noticeably larger anisotropic thermal expansion than BaCeO 3 . The results indicate that high tolerance to Cr-gaseous species should be considered as an important criterion for further development of materials for proton-conducting SOFCs.
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
Biosensors-Basel
·
2022
·Vol. 12
·期 9
·760
·
IF 5.743
Haijun Du,Yan Zhang,Xin Wang,Huali Hu,Jixing Ai,Huanxi Zhou,Xia Yan,Yang Yang,Zhiwei Lu
The determination of plant growth regulators is of great importance for the quality monitoring of crops. In this work, 4-bromophenoxyacetic acid (4-BPA), one of the phenoxyacetic acids, was detected via the electrochemical method for the first time. A CeO2-decorated electrochemical exfoliated graphene (eGr) composite (CeO2/eGr) was constructed as the sensor for sensitive detection of 4-BPA due to the synergistic effect of the excellent catalytic active sites of CeO2and good electron transference of the eGr. The developed CeO2/eGr sensor displayed a good linearity in a wide range from 0.3 to 150 μmol/L and the lowest detection limit of 0.06 μmol/L for 4-BPA detection. Electrochemical oxidation of 4-BPA follows a mix-controlled process on the CeO2/eGr electrode, which involves 2e in the transference process. This developed CeO2/eGr sensor has excellent repeatability with a relative standard deviation (RSD) of 2.35% in 10 continuous measurements. Moreover, the practical application of the sensor for 4-BPA detection in apple juice has recoveries in the range of 90–108%. This proposed CeO2/eGr sensor has great potential for detecting plant growth regulators in the agricultural industry.Keywords:plant growth regulators;4-bromophenoxyacetic acid;electrochemical determination;lowest detection limit;CeO2/eGr composite
研究领域:
农业科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemSusChem
·
2024
·
IF 7.5
Yanan Wei,Jianming Pan,Xu Yan,Yanli Mao,Yunlei Zhang
Graphical The AuPd/CeO 2 catalyst was employed for the oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), showing that high oxygen vacancy of CeO 2 and electron-rich state of interfacial Au−Pd−CeO 2 can strengthen the adsorption and activation of HMF and molecular oxygen, greatly promoting the elimination of β -hydride for the conversion of HMF to FDCA. The design of high activity catalyst for the efficiently conversion of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) gains great interest. The rationally tailoring of electronic structure directly affects the interaction between catalysts and organic substrates, especially molecular oxygen as the oxidant. This work, the bimetallic catalysts AuPd/CeO 2 were prepared by the combining method of chemical reduction and photo-deposition, effectively concerting charge between Au and Pd and forming the electron-rich state of Au. The increasing of oxygen vacancy concentration of CeO 2 by acidic treatment can facilitate the adsorption of HMF for catalysts and enhance the yield of FDCA (99.0 %). Moreover, a series of experiment results combining with density functional theory calculation illustrated that the oxidation performance of catalyst in HMF conversion was strongly related to the electronic state of interfacial Au−Pd−CeO 2 . Furthermore, the electron-rich state sites strengthen the adsorption and activation of molecular oxygen, greatly promoting the elimination of β -hydride for the selective oxidation of 5-hydroxymethyl-2-furancarboxylic acid (HMFCA) to FDCA, accompanied with an outgoing FDCA formation rate of 13.21 mmol ⋅ g −1 ⋅ min −1 at 80 °C. The perception exhibited in this research could be benefit to understanding the effects of electronic state for interfacial sites and designing excellent catalysts for the oxidation of HMF.
研究领域:
催化化学
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材料科学
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理论计算化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Fuel Cells
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2022
·
IF 2.948
Yanqi Hao,Lin Ge,Siew Hwa Chan
Looking for non-noble metal catalysts with low cost, high activity, and high stability to replace platinum in oxygen reduction reaction (ORR) has aroused great concern. According to previous studies, Fe-N x /C material is one of the most promising non-noble metal catalysts for ORR. In this study, new Fe-N x /C material was synthesized by introducing CeO 2 and Fe 3 O 4 nanoparticles into a Fe-N x /C material derived from ZIF-8 as precursors. The new material was called CeO 2 -Fe 3 O 4 @Fe-N/C catalyst and the activity of the catalyst was found to be significantly improved in 0.1 mol L −1 KOH. The half-wave potential of CeO 2 -Fe 3 O 4 @Fe-N/C (0.892 V) is higher than that of Pt/C by 67 mV. In the stability test, the half-wave potential of CeO 2 -Fe 3 O 4 @Fe-N/C was only reduced by 4 mV after 5,000 cycles. The high performance is attributed to the introduction of CeO 2 and Fe 3 O 4 , which gives CeO 2 -Fe 3 O 4 @Fe-N/C enhanced electrocatalytic activity and long-term stability. This approach makes CeO 2 -Fe 3 O 4 @Fe-N/C a promising candidate for cathode catalysts in renewable energy conversion devices.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）