RSC Advances
·
2019
·Vol. 9
·期 24
·13696-13704
·
IF 3.049
Hong Lei,Ruheng Zheng,Yeping Liu,Jiacheng Gao,Xiang Chen,Xiaoliang Feng
Hydrogenation of CO2 to chemicals is of great importance in the reduction of greenhouse gas emission. And the interaction and/or the boundary between Cu and ZnO played a crucial role in the performance of the Cu–ZnO catalyst for CO2 hydrogenation to methanol. In this work, cylindrical shaped ZnO was first synthesized via controlled hydrothermal precipitation of Zn(CO2CH3)2·2H2O, and Cu was further deposited on ZnO via in situ reduction in aqueous solution. Characterizations indicated that the crystallization degree of ZnO decreased with the increasing content of Cu, while the exposed surface area of Cu exhibited a volcano shaped curve. It was found that the cylindrical shaped ZnO combined Cu catalysts were active for the hydrogenation of CO2, and the space time yield of methanol reached 0.50 g-MeOH (g-cat h)−1 at H2/CO2 = 3, 240 °C, 3.0 MPa, and 0.54 mol (g-cat h)−1, but the methanol selectivity decreases with the reduction of the (002) polar plane of ZnO. The conversion of CO2 and methanol selectivity were discussed with the detected exposed Cu surface area and the number of oxygen vacancies.
研究领域:
化学工程
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催化科学
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产品关联
DOI
PubMed
高影响因子
Catalysts
·
2022
·Vol. 12
·期 5
·534
·
IF 4.501
Zhaohui Teng,Shan Huang,Na Li,Qulan Zhou
Rice husk ash (RHA) has potential as a supporter of catalysts. In this research, we studied the activity and SO2tolerance of RHA-based Fe-Cu oxide in the reduction of NO by CO. Characterization methods were employed to study the properties of the catalysts and their SO2tolerance. Activity and SO2resistance were also tested at different temperatures. We recommend two catalysts with SO2resistance ability: Fe0.67Cu0.33/RHA (the highest catalytic activity) and Fe0.8Cu0.2/RHA. The NO removal rate hardly changed with the addition of SO2and was kept at about 100%. However, the CO conversion rate decreased with increasing SO2at the lower reaction temperatures, which may be due to the formation of sulfites. Fortunately, the deactivation was reversible and can be reduced with an increase in the reaction temperature. The results of our research may help promote the application of CO-SCR.Keywords:rice husk ash;Fe-Cu catalysts;NO reduction;SO2resistance;CO-SCR
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
·
IF 20.2
Tianyi Wu,Jiaxuan Chen,Lingyue Liu,Xiaolei Qu,Shourong Zheng,Dongqiang Zhu
Electrochemical reduction of nitrate to ammonia (NH 3 ) provides an attractive approach to accomplish resource utilization of pollutants, while exploring efficient catalysts with high catalytic activity and NH 3 FE at low applied potentials remains great challenging. Herein, we constructed a three-dimensional Cu 3 P/Cu catalyst and studied its catalytic performances in electrochemical nitrate reduction reaction . The Cu 3 P/Cu catalyst with finely balanced metallic Cu and Cu 3 P sites exhibits a high NH 3 yield of 4.27 mg h −1 cm −2 after 1 h reaction at a low applied potential (-0.05 V vs RHE), outperforming most of previously reported Cu-based catalysts. DFT calculations demonstrate the favored reduction of nitrate to nitrite on metallic Cu and hydrogenation of nitrite to NH 3 on Cu 3 P. This study opens up new opportunities for the application of Cu 3 P/Cu catalyst as a robust tandem electrocatalyst in the large-scale production of NH 3 through electrochemical reduction with low energy consumption.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2018
·Vol. 124
·期 2
·587-601
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IF 1.515
Wang Tao,Zhang Xinyu,Liu Jun,Liu Hanzi,Sun Baomin
NO conversion using dielectric barrier discharge (DBD) plasma with different catalysts was investigated. Cu/TiO 2 , Cu/Al 2 O 3 , Cu/ZSM-5, Cu/CNTs and Cu/AC catalysts were prepared by incipient wetness impregnation with 4 wt% Cu loaded. BET, SEM, XRD, XPS, H 2 -TPR, NH 3 -TPD were used to measure and evaluate various catalysts. Compared with the plasma only process, the combination of plasma with different catalysts significant improved the NO conversion rate. The highest NO conversion rate of 76% could be achieved with Cu/ZSM-5 catalyst at the energy density of 184 J/L. The results indicate that Cu species over the support ZSM-5 can produce high concentrations of CuO, largest specific surface area, largest amounts of acidity and lowest reduction temperature (209 °C), these factors conducive to plasma-catalyst reaction. Besides, Cu/TiO 2 and Cu/Al 2 O 3 catalysts exhibited excellent NO conversion at the low energy density because of the low thermal stability. After plasma-catalyst reaction, the reducibility of CuO and Cu 2 O over supports decreased and the peak position of acid sites shifted to lower temperature.
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 Science & Technology
·
2019
·Vol. 9
·期 10
·2673-2681
·
IF 5.726
Bing Hu,Yazhi Yin,Zixin Zhong,Dengdeng Wu,Guoliang Liu,Xinlin Hong
Maximizing the Cu–ZnO interface is regarded as the best strategy to promote methanol synthesis activity over CuZn catalysts. Reducing the ZnO particle size can enhance the Cu–ZnO interaction, but its synthesis with a sub-5 nm size still remains a challenge. Moreover, the fabrication of an active powder catalyst with an inverse ZnO/Cu configuration is still very rare. In this work, we report a facile synthesis of inverse ZnO/Cu catalysts by direct calcination of Cu@ZIF-8 (zeolitic imidazolate framework-8). The particle size of ZnO and Cu can be tuned by changing the Cu loading as well as the calcination temperature. Importantly, inverse ZnO/Cu catalysts with sub-5 nm ZnO were obtained under gentle calcination at 623 K. In the CO2 hydrogenation reaction, the highest methanol synthesis activity reached 933 g kgcat−1 h−1 at 533 K and 4.5 MPa, with a high turnover frequency (TOF) of 0.013 s−1, over an optimized C2Z-623 catalyst, which exceeds the commercial CuZnAl catalyst (HiFuel R120, Johnson Matthey) and has ranked the top reported value over advanced CuZn catalysts under comparable conditions. Such excellent activity is attributed to the inverse structure of Cu particles covered by sub-5 nm ZnO, which promotes the intimate Cu–ZnO interface with enhanced SMSI. Moreover, we find that the methanol turnover frequency (TOF) monotonically increases with decreasing the particle size of ZnO as well as Cu. It is proposed that reducing the ZnO size favors the spillover of reducible ZnOx species onto the Cu surface while lowering the Cu size is responsible for the enhanced amount of exposed Cu steps for accommodating Zn species, both of which could facilitate the formation of Zn covered Cu steps as active sites for methanol synthesis.
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
Processes
·
2024
·Vol. 12
·期 9
·1912
·
IF 2.8
Bowen Lu,Huiying Sang,Liang Liu,Zhijian Yu,Yaqin Guo,Yongqing Xu
The catalytic applications of micron Cu powder are limited due to its large particle size and small specific surface area. Modifying micro-Cu powder to achieve a high catalytic performance is a challenge in the application of micron copper. In this work, micro-Cu was used to synthesize a CeO2–Cu catalyst, and the phase composition and surface pore structure were analyzed using XRD, BET, etc. The CO2hydrogenation performance of the CeO2–Cu catalyst was analyzed in comparison with CeO2and Cu, and we found that the CeO2–Cu catalyst exhibited a synergistic effect between Cu and cerium, resulting in a much higher hydrogenation performance at 500 °C than CeO2or Cu alone. H2-TPR and TEM characterization revealed that the CeO2–Cu catalyst formed interfacial interactions with a relatively large Ce–Cu interface, where cerium oxide could promote the reduction of CuO and lower the reduction temperature. Additionally, cerium oxide formed a confinement structure for Cu, and the CeO2–Cu catalyst exhibited a higher oxygen vacancy concentration, thereby promoting the CO2hydrogenation performance. Cu–CeO2interaction provides valuable insights into the catalytic application of micron Cu powder.
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
Journal of CO2 Utilization
·
2021
·
IF 7.132
Bowen Lu,Yongqing Xu,Zewu Zhang,Fan Wu,Xiaoshan Li,Cong Luo,Liqi Zhang
Cu-based catalysts had been widely used in CO 2 hydrogenation process for their excellent performance and high selectivity. Micron-sized Cu powder obtained by ball milling exhibited poor CO 2 activity for its large particle size and small specific surface area, limited its catalytic application. In this work, micron Cu powder was modified with CeO 2 species synthesized from different cerium precursor salts via a solution auto-combustion method to investigate CO 2 hydrogenation activity. This work revealed that CeO 2 species formed from cerium acetate precursor salt achieved excellent CO 2 performance (1.64 mol/g cat .h at 400 °C), which was 3.8 times and 6000 times higher than that from cerium nitrate salt or cerium chloride salt, respectively. Interestingly, a thick dense CeO 2 shell would be formed on micron Cu generated from cerium(III) chloride precursor salt, which inhibited CuO x reduction and had the opposite effect for RWGS reaction. In addition, the CuO x species in CeO 2 @Cu synthesized from cerium chloride salt resulted in the CH 4 selectivity. The enhancement performance of the CeO 2 @Cu prepared from cerium acetate salt and cerium nitrate salt could be attributed to the oxygen defects formed around the Cu-Ox-Ce interface area and metallic Cu in the RWGS reaction. Cerium precursor salts enhanced the structural integrity of CeO 2 @Cu and played a vital role in RWGS reaction. These results will support a new direction for exploring micron Cu powder in Cu-based catalysts for CO 2 utilization.
研究领域:
化学工程
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材料科学
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
Nano-Micro Letters
·
2020
·Vol. 12
·期 1
·1-13
·
IF 12.264
Pan Zhengbin,Han Ershuan,Zheng Jingui,Lu Jing,Wang Xiaolin,Yin Yanbin,Waterhouse Geoffrey I. N.,Wang Xiuguo,Li Peiqiang
Flower-like CeO 2 nanoparticles enhance the performance of CuO nanoparticle/Cu.
The system benefits from the heterojunction between p-type CuO and n-type CeO 2 .
The selective reduction of CO 2 to methanol on the target catalyst is studied.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Tianyi Wu,Jiajia Hu,Yuqiu Wan,Xiaolei Qu,Shourong Zheng
Bromate is a commonly identified carcinogenic and genotoxic disinfection byproduct in water. In the present work, bimetallic Ru-Cu catalyst supported on carbon nanotube (RuCu/CNT) was prepared and the structural properties of the catalysts were characterized. The results show that the presence of Ru enhances the dispersion and reduction of Cu particles in the RuCu/CNT catalyst in comparison with the monometallic Cu catalyst supported on CNT (Cu/CNT). For electrocatalytic reaction on Cu/CNT, bromate is reduced on metallic Cu surface via a redox process. For Ru/CNT, highly active H* radicals are generated on metallic Ru surface via the Volmer process and are used for bromate reduction. As for the RuCu/CNT, bromate is reduced through two main pathways, including direct redox reaction on metallic Cu and indirect reduction by active H* radicals on Ru surface. Accordingly, RuCu/CNT exhibits the highest catalytic activity , ascribed to the synergistic effect between metallic Ru and Cu. Furthermore, the bimetallic catalyst displays much higher catalytic efficiency as compared with previously reported results. The pH, initial bromate concentration, in-situ electrochemical reduction of the electrodes and working potential have strong impacts on the removal efficiency of bromate on RuCu/CNT.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2025
·
IF 13.5
Lele Feng,Xueying Bai,Jifeng Pang,Hongchen Cao,Xiaoyan Liu,Wenhao Luo,Xiaofeng Yang,Pengfei Wu,Mingyuan Zheng
Ethanol dehydrogenation is a vital elementary step in ethanol upgrading, for which Cu-based alloy catalysts are the most promising candidates. Nevertheless, elucidating the underlying reasons for the synergistic effect between alloying components and host metals remains challenging due to the intrinsic structural complexity and dynamic evolution of alloy catalysts under operational conditions. Herein, single-atom Pd modified Cu-MFI catalysts with well-defined structures were designed for ethanol dehydrogenation to acetaldehyde and hydrogen. Comprehensive characterizations using aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (AC-HAADF-STEM), X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that Pd atoms are isolated by surrounding Cu atoms with a coordination number of 9–10, forming −0.36 e charged single-atom sites and being uniformly dispersed on the surface of Cu catalysts. The newly generated Pd δ − and Cu δ + sites synergistically reduced the activation energy barrier for C–H bond cleavage in ethanol. These sites simultaneously enhanced hydrogen adsorption and H–H bond coupling, leading to improved ethanol conversion and acetaldehyde productivity over Pt/Cu-MFI catalysts.
研究领域:
催化化学
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材料科学
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表面科学
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产品关联
DOI
高影响因子
Asia-Pacific Journal of Chemical Engineering
·
2017
·Vol. 12
·期 3
·422-431
·
IF 0.836
Yuan Wang,Wei Zhu,Shengya Sang,Lijing Gao,Guomin Xiao
Aqueous-phase processing of biomass-derived furfural is one of the promising ways to convert biomass into useful chemicals. Supported metal catalysts are crucial in the aqueous-phase hydrogenation of furfural. Understanding the effect of acid and basic properties of supports on the performance of the catalysts will help understand the reaction pathways and develop more efficient catalysts. Here, a series of Cu-based catalysts with different supports (Al 2 O 3 , ZnO, SiO 2 , MgO, and ZSM-5) have been investigated in hydrogenation of furfural in aqueous phase. The properties of the supports have been characterized by X-ray diffraction, N 2 adsorption–desorption, transmission electron microscope, H 2 temperature-programmed reduction, and CO 2 and NH 3 temperature-programmed desorption. The results show that pure acid support leads to the formation of oligomers and pure basic support results in furfuryl alcohol as the main product. And the mass balance in reaction system catalyzed by Cu-based catalysts with higher acidity amount is lower. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Shuanglin Jia,Wenhao Yang,Hao Liu,Xiao Chen,Jingjie Luo,Changhai Liang
Furfural is an indispensable platform compound derived from biomass resource and can be hydrogenated to produce a series of high value-added chemicals. In order to overcome the disadvantages of low selectivity and poor stability during furfural hydrogenation, design of promising Cu catalysts with well-disentangled catalytic theory becomes a hot topic. In this work, a series of Cu-M/Al 2 O 3 (M=Fe, Co, Ni, Ce) catalysts were prepared by sol-gel method to make a uniform ternary metal composition. Distinctive product distribution for the catalytic transfer hydrogenation of furfural was obtained depending on the specific Cu-M/Al 2 O 3 system. Among them, the Cu-Fe/Al 2 O 3 displayed superior selectivity of 2-methylfuran compared to any other catalysts. The introduced metal additive acted as the electron donor to regulate the surface dispersion of Cu species. Higher percentage of surface Cu 0 +Cu + species were formed on Cu-Ce/Al 2 O 3 and Cu-Fe/Al 2 O 3 , accounting for the much lower activation energy and better dissociation ability for isoproponal. If Cu-Ni/Al 2 O 3 or Cu-Ce/Al 2 O 3 was used as the catalyst, hydrogenation happened on the furan ring. Whilst Cu-Co/Al 2 O 3 was more preferentially used to produce 2-pentanol and 2-pentanone, with large amount of copper species in oxidative states. The yield of 2-MF reached 84 % at 220 ºC in N 2 at ordinary pressure by Cu-Fe/Al 2 O 3 with the specific rate of 106.8 mmol FAL ·g Cu −1 ·h −1 .
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子