JOURNAL OF THE ENERGY INSTITUTE
·
2021
·
IF 6.186
Riyang Shu,Zhuojie Zhong,Hongyun You,Zhipeng Tian,Ying Chen,Longlong Ma
Hydrodeoxygenation (HDO) is an important pathway for lignin-oil upgradation to produce high quality liquid fuels, in which the high-active catalyst is the key point to achieve a high HDO efficiency. In this study, Ru/TiO 2 , Ru/CeO 2 and Ru/TiO 2 –CeO 2 catalysts were synthesized by a novel photochemical method with a high Ru dispersion and used for the HDO of lignin-derived phenolic compounds. Among these three catalysts, Ru/TiO 2 –CeO 2 showed a better performance than Ru/TiO 2 and Ru/CeO 2 . And guaiacol was transformed into cyclohexane with conversion and product selectivity close to 100 % at 230 °C under 1 MPa hydrogen atmosphere. Ru/TiO 2 –CeO 2 took the advantages of Ru/TiO 2 and Ru/CeO 2 , namely high Ru metal dispersion, plenty of medium strength acid sites and abundance of oxygen vacancy , which promoted the guaiacol adsorption and the HDO catalytic activity . Moreover, Ru/TiO 2 –CeO 2 catalyst showed an effective upgrading of other lignin-derived phenolic compounds. And the lignin-oil also enabled to be upgraded efficiently, producing a high content of hydrocarbons and alkylphenols.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Shuaiqi Zhao,Jiajin Lin,Wenqiang Gong,Aihua Xu,Xiaoxia Li,Yongcai Qiu
Pt-based catalysts are one of the most extensively used heterogeneous catalysts for the degradation of pollutants, and regulating electron-metal-support interaction (EMSI) is an efficient strategy to enhance the performance of Pt-based catalysts. Herein, we introduced a quenching technique for regulating the EMSI of Pt-CuO/CeO 2 catalysts to significantly boost its CO catalytic activity. The EMSI optimized by quenching was determined to promote the electron redistribution between Pt and CuO/CeO 2 via Cu–O-Pt structure, thus forming more electron-rich Pt species and enhancing the surface oxygen species activity. From comprehensive characterization investigations, we confirmed that the superior activity arouse from the moderate Pt 0 /Pt 2+ ratio, in which CO molecules were preferentially adsorbed on the electron-rich Pt sites and reacted with active oxygen species from PtO x or CuO/CeO 2 , accelerating the whole CO catalytic process. Our finding provided a new inspiration to control EMSI of Pt-based catalysts and widened the application of quenching chemistry in heterogeneous catalysis.
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高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Jingjing Tan,Jing He,Kuan Gao,Shanhui Zhu,Jinglei Cui,Long Huang,Yulei Zhu,Yongxiang Zhao
The hydrogenation of furfural to furfuryl alcohol in liquid was performed over Cu/CeO 2 catalyst with different morphology that was nanorod (CeO 2 -R), nanocube (CeO 2 -C) and nanopolyhedron (CeO 2 -P), respectively. It was observed that the Cu/CeO 2 -R catalyst exposed (1 1 0) crystal plane owns more oxygen vacancies and metal sites of Cu 0 in comparison with the catalyst of Cu/CeO 2 -P and Cu/CeO 2 -C. Meanwhile, it exhibited superior catalytic performance for furfural hydrogenation to furfuryl alcohol with a high yield of 98 % at 100 °C, 2 MPa H 2 within 4 h. The structure–activity relationship demonstrated that the catalyst intrinsic activity (TOF) is positively related to the concentration of oxygen vacancies and the metal sites of Cu 0 on its surface. DFT calculations and in-situ FTIR confirmed that Cu/CeO 2 -R (1 1 0) catalyst with more oxygen vacancy is in favor of the adsorption and activation of furfural (C O) on the catalyst surface compared with Cu/CeO 2 -P (1 1 1) and Cu/CeO 2 -C (1 0 0). Accordingly, the remarkable efficiency of Cu/CeO 2 -R catalyst can be assigned to the synergistic catalysis between the surface Cu 0 and the oxygen vacancies. Cu 0 was used to adsorb and activate H 2 , whereas the oxygen vacancies facilitate the adsorption of C O by O on the surface of the catalyst.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 36
·23118-23128
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IF 4.036
Luxin Zhang,Xu Xing,Ruijun Sun,Meng Hu
Selective catalytic conversion of carbohydrates to 5-ethoxymethylfurfural (EMF) is a critical approach to the biorefinery. In this work, solid acid catalysts of γ-AlOOH and CeO2@B2O3 were used to convert carbohydrates to EMF in a one-pot process, performed in an ethanol/DMSO solvent system. The synergistic effect of γ-AlOOH and CeO2@B2O3 was studied. Furthermore, the morpho-structural properties of the catalysts were characterized, and the effects of reaction time, reaction temperature, catalyst load, and the amount of cosolvent on the conversion of glucose to EMF were examined and optimized. Under the reaction conditions of 170 °C for 20 h, glucose, sucrose, cellobiose, inulin and starch were used as raw materials, and the EMF yield range was 9.2–27.7%. The results showed that the synergistic effect of γ-AlOOH and CeO2@B2O3 further causes the combination of multiple acid sites with different types and strength distributions. Particularly, the collaboration between weak, medium-strong, and strong acid, as well as between Lewis and Brønsted acidity, is of great significance for EMF generation. The reusability experiments showed that the combined catalytic system was easily separated and maintained catalytic activity for five successive reactions without further intermediate regeneration steps. This work provides a promising route for the catalytic conversion of biomass-derived carbohydrates into EMF.
研究领域:
化学工程
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催化
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可再生能源
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生物化学
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DOI
PubMed
高影响因子
APPLIED ENERGY
·
2020
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IF 8.848
Hao Sun,Yingjie Li,Xianyao Yan,Jianli Zhao,Zeyan Wang
The calcium looping energy storage is a promising technique for thermochemical energy storage in concentrated solar power plants. Nevertheless, natural CaO-based materials, such as limestone, have an obvious decline in energy storage capacity during cyclic CaO/CaCO 3 energy storage. In this work, a novel Al 2 O 3 /CeO 2 co-doped CaO-based material for energy storage is synthesized by a wet-mixing method. And the thermochemical energy storage performance of the Al 2 O 3 /CeO 2 co-doped CaO-based material under high carbonation pressure is studied. Additionally, the influences of the doping amount of Al 2 O 3 /CeO 2 , the carbonation pressure and the temperature on the energy storage performance of the synthetic material are discussed. The main compositions of the synthetic material are CaO, Ca 12 Al 14 O 33 and CeO 2 . When 5 wt% Al 2 O 3 and 5 wt% CeO 2 are doped on CaO, the synthetic material shows the highest and most stable energy storage capacity under the carbonation pressure of 1.3 MPa during 30 cycles. The Ce 3+ ions existing on the surface of the synthetic material can create oxygen vacancies on the surface of CaO and increase the amount of surface adsorbed oxygen, which facilitates the carbonation of CaO. In addition, the synthetic material possesses strong basicity and provides a large surface area and pore volume during the multicycle energy storage. The high energy storage performance of the synthetic material is attributed to the high pressure in the carbonation process, the good support of Ca 12 Al 14 O 33 and the catalytic function of CeO 2 . The synthetic material can reduce the overall cost in concentrated solar power plants, thus it appears promising.
研究领域:
材料科学
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可再生能源
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化学工程
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2023
·
IF 5.5
Lu Ji,Fang Li,Conghui Che,Wei Xue,Qiusheng Yang,Xiaoshu Ding,Dongsheng Zhang,Xinqiang Zhao,Yanji Wang
In the reaction of dimethyl carbonate (DMC) and 2,4-diaminotoluene (TDA), Au/CeO 2 exhibits higher selectivity than CeO 2 for dimethyl toluene-2,4-dicarbamate (TDC). However, its catalytic activity drops after H 2 reduction (denoted as Au/CeO 2 -R). The characterization results illustrate that Au exists as a single atom with the primary species as Au δ+ in Au/CeO 2 , forming Ce x Au 1−x O 2 structure similar to solid solution. Whereas for Au/CeO 2 -R catalyst, Au mainly exists as Au 0 , forming the Au-O-Ce structure on CeO 2 surface. Significantly, the strong interaction between Au and CeO 2 increases Ce 3+ and oxygen vacancies content, as well as modulates their acidic property. However, the catalytic activity of Au/CeO 2 -R is found to be lower than Au/CeO 2 as the species formed by DMC dissociation on its surface are not easily desorbed. Other transition metals supported on CeO 2 are also prepared, wherein Pt/CeO 2 and Pd/CeO 2 exhibit good TDC selectivity. In the end, the electronegativity and catalytic activity of metals are correlated.
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高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Zixiang Su,Hehe Wei,Longtao Zhang,Hui Li,Ping Liu,Zhenshan Hou,Xueqing Gong
The electrocatalytic oxygen reduction reaction (ORR) is the key bottleneck of fuel cells and rechargeable metal-air batteries , and recently, metal nitrogen complex carbon (M N C) demonstrates great potential in these fields. However, the complex and easily degraded M N C structure often results in inferior activity and poor durability in electrolysis. Herein, we fabricate a catalyst of h-CeO 2 @CoNC through the extended Stöber method and subsequent pyrolysis , involving the hollow CeO 2 as the core and Co N C as the shell. The h-CeO 2 @CoNC catalyst exhibits notable ORR catalytic performances in 0.1 M KOH with a half-wave potential of 0.82 V and excellent durability, attributed to the synergistic interaction between CeO 2 and Co N C matrix. Specifically, the inner layer of CeO 2 is principally responsible for enhancing the chemical stability and the outer one of Co N C matrix is beneficial to boosting the ORR catalytic activity. This work provides an efficient preparation approach and further insight of rational design of the unique M N C catalysts for energy storage.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Yiqing Zeng,Yanan Wang,Plaifa Hongmanorom,Zhigang Wang,Shule Zhang,Jiatang Chen,Qin Zhong,Sibudjing Kawi
Highly-efficient CeO 2 -TiO 2 -based catalyst is an attractive alternative to traditional V 2 O 5 -based catalysts for selective catalytic reduction of NO x by NH 3 (NH 3 -SCR). Herein, we construct an efficient and stable P-doped CeO 2 /TiO 2 ( y CeTi-P x ) catalyst by dispersing CeO 2 on strongly acidic and highly stable mesoporous P-doped TiO 2 (Ti-P x ). The characteristic structure of Ti-P x causes highly dispersed CeO 2 , strong active component-support interaction, and abundant surface active oxygen and acid sites on CeTi-P catalyst. Therefore, y CeTi-P x catalyst exhibits much higher catalytic activity than y CeTi catalyst at temperature of 200–450 °C. The y CeTi-P x catalysts show high activity in the presence of H 2 O and strong resistance to H 2 O + SO 2 at medium-high temperature, implying that they have great industrial application prospects. Different P/Ti ratio and CeO 2 loading content were investigated. Excessive P doping can block the Ce 4+ /Ce 3+ redox couple, and suppress redox sites on y CeTi-P x catalyst. Additionally, increasing CeO 2 content can reduce the NH 3 capacity of y CeTi-P x catalyst. By controlling the P/Ti ratio and CeO 2 loading content, surface acid sites and redox sites on y CeTi-P x catalyst can be balanced to obtain the best catalytic activity. This work demonstrates a feasible method in adjusting acid sites and redox sites on CeTi catalyst, which ultimately contributes to the new design of CeO 2 -TiO 2 -based catalyst.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
CATALYSIS TODAY
·
2020
·
IF 5.825
Mengmeng Jin,Linhao Yu,Hong Chen,Xueli Ma,Kai Cui,Zhe Wen,Zewei Ma,Yushuai Sang,Mengmeng Chen,Yongdan Li
Ce oxide-based catalysts with different molar ratio of Co/Ce (denoted as CoCe-x, x represents the Co to Ce ratio) were examined as the catalyst of 5-hydroxymethylfurfural (5-HMF) oxidation to 2,5-furandicarboxylic acid (FDCA). The Co to Ce ratio, catalyst amount and reaction temperature all have remarkable effects on yield and selectivity. Complete conversion of 5-HMF with 86.3 % selectivity of FDCA has been achieved over the CoCe-0.15 catalyst at 130 °C with 0.6 MPa O 2 pressure (gauge) for 4 h. The good performance is attributed to the high specific surface area and the high oxygen vacancy concentration to promote the mobility and adsorption of oxygen species. In addition, the CoCe-0.15 catalyst is reused for five times without significant activity loss. Finally, the reaction mechanism over the CoCe-0.15 catalyst under base-free condition is discussed. 5-HMF is oxidized by the lattice oxygen via Mars-van Krevelen mechanism with the redox of Ce 4+ /Ce 3+ and Co 3+ /Co 2+ , and the lattice oxygen is replenished by adsorbing and activating O 2 molecules.
研究领域:
化学工程
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催化材料科学
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产品关联
DOI
高影响因子
APPLIED PHYSICS LETTERS
·
2014
·Vol. 105
·期 5
·
IF 3.515
Zhang Liang,Chen Shuo,Yuan Shuai,Wang Dongrui,Hu Peng-Hao,Dang Zhi-Min
Nanocomposite films with cerium oxide (CeO 2 ) nanoparticles as functional fillers and polystyrene (PS) as polymer matrix were prepared using solution casting method. Physical properties including both weak frequency dependence of dielectric permittivity and low dielectric loss were experimentally discovered in the CeO 2 /PS nanocomposite films. To improve the dielectric properties of films further, the surface of CeO 2 nanoparticles was treated by H 2 O 2 to increase the homogeneity of the nanocomposite film, which was confirmed by scanning electron microscopy (SEM) results. Furthermore, it was found that both the filler size and the filler volume fraction played a role on the dielectric properties of the nanocomposite films.
研究领域:
材料科学
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物理学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 21
·12806-12817
·
IF 2.599
Zhong Xi,Zhou Yuming,He Man,Tong Yuan,Fan Lidan,Cai Zhilan
In this study, a simple, convenient and green approach for the preparation of organosiloxane-coated SiO 2 /CeO 2 (SiO 2 /CeO 2 /poly(VTMS)) with multilayered hierarchical structure is demonstrated by consecutive surface cerium deposition and organosiloxane grafting on the bare silica spheres. The results of the UV–Vis spectrum and photoluminescence analysis suggest that the fillers may be potentially applied in UV absorbers and bioimaging materials. Moreover, the optical diffusers based on the multilayered spheres can be prepared via a solvent-free UV curing process and exhibit enhanced properties like suitable light transmittance, good diffusion capacity and low-incident angle dependence, which are critical for the optical diffusers. In addition, when the concentration of the fillers was 15 wt%, the optical diffusers presented superior light-diffusing properties among all the as-prepared samples. Thus, the films based on the SiO 2 /CeO 2 /poly(VTMS) with multilayered hierarchical structure may open up new possibilities in applications as multifunctional light diffusion films in liquid crystal displays.
研究领域:
材料科学
·
光学工程
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DOI
高影响因子
Catalysis Science & Technology
·
2018
·Vol. 8
·期 6
·1621-1631
·
IF 5.365
Yuxi Gao,Xiaodong Wu,Robin Nord,Hanna Härelind,Duan Weng
The sulphur resistance and regeneration strategy of soot oxidation catalysts are critical to the application of catalytic diesel particulate filters (CDPFs). In the present work, Pt/MnOx–CeO2/Al2O3, Pt/Al2O3 and MnOx–CeO2/Al2O3 catalysts were sulphated and regenerated with ammonia. The soot oxidation activity of poisoned Pt/MnOx–CeO2/Al2O3 was recovered completely after 30 min reduction in 500 ppm NH3 at 550 °C. The amount, distribution and structure of sulphates were studied comprehensively for the sulphated and regenerated samples by thermogravimetric analysis (TGA), infrared (IR) spectroscopy, CO chemisorption and transmission electron microscopy (TEM). The NO oxidation of Pt catalysts was found to depend strongly on the particle size distribution, surface exposure and oxidation state of the precious metal. This, as well as the effect of the remaining surface sulphates, helped the regenerated catalysts achieve even higher catalytic activity for soot oxidation.
研究领域:
催化材料
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环境科学
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化学工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）