Science China-Chemistry
·
2019
·Vol. 62
·期 12
·1710-1719
·
IF 6.085
Wang Guishuo,Luo Ran,Yang Chengsheng,Song Jimin,Xiong Chuanye,Tian Hao,Zhao Zhi-Jian,Mu Rentao,Gong Jinlong
Metal oxide-promoted Rh-based catalysts have been widely used for CO 2 hydrogenation, especially for the ethanol synthesis. However, this reaction usually suffers low CO 2 conversion and alcohols selectivity due to the formation of byproducts methane and CO. This paper describes an efficient vanadium oxide promoted Rh-based catalysts confined in mesopore MCM-41. The Rh-0.3VO x /MCM-41 catalyst shows superior conversion (~12%) and ethanol selectivity (~24%) for CO 2 hydrogenation. The promoting effect can be attributed to the synergism of high Rh dispersion by the confinement effect of MCM-41 and the formation of VO x -Rh interface sites. Experimental and theoretical results indicate the formation of til-CO at VO x -Rh interface sites is easily dissociated into *CH x , and then *CH x can be inserted by CO to form CH 3 CO*, followed by CH 3 CO* hydrogenation to ethanol.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
Carbon Capture Science & Technology
·
2023
·
IF 0
Wufeng Wu,Jiang Fan,Dongyue Wang,Yali Zhao,Xinglei Zhao,Yanying Wei
MOF membranes exhibit impressive performance in gas separation due to their large surface area, controllable pore size and unique affinity. Here, the ultrathin UiO-66-NH 2 polycrystalline membranes with thickness of ∼320 nm are successfully prepared within 1 h using a combination of ultrasound-assisted and microwave synthesis strategies. During the reaction, high-density small MOF nuclei are produced by sodium formate ultrasound-assisted, which act as sufficient nucleation sites for heterogeneous nucleation during membrane growth, aiming for development of a continuous MOF membrane on the porous substrate. The obtained UiO-66-NH 2 membrane shows an ideal CO 2 /CH 4 selectivity of 40 due to the enhanced the interaction between CO 2 molecules and the membrane. Moreover, the narrowed pore structure further hinders the diffusion of larger-sized molecules owing to -NH 2 occupying the pore channels, resulting in elevated CO 2 /CH 4 selectivity. Compared to many other MOF membranes, the UiO-66-NH 2 polycrystalline membranes exhibit a well balance of gas permeance and CO 2 /CH 4 selectivity, which presents a new route for CO 2 capture.
研究领域:
材料科学
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化学工程
·
环境科学
✓ 已验证
DOI
Nanoscale
·
2015
·Vol. 8
·期 2
·1140-1146
·
IF 7.394
Chunmei Gao,Shaoyu Lü,Mingzhu Liu,Can Wu,Yun Xiong
The synthesis and properties of CO2 responsive and fluorescent dendritic polymers, poly(amido amine)/Pluronic F127 (PAMAM/F127), are reported in this paper. The morphologies and sizes of PAMAM/F127 dendritic polymers were investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM). PAMAM/F127 dendritic polymers showed unimolecular micelle morphologies at low concentrations, and changed to multimolecular micelles at higher concentrations. Additionally, fluorescence spectra and confocal laser scanning microscopy images showed that PAMAM/F127 dendritic polymers exhibited a fluorescent enhancement response to the presence of CO2. Apart from that, the release behavior of PAMAM/F127 gels under simulated body fluids was investigated by choosing curcumin as the hydrophobic drug. The results indicated that PAMAM/F127 dendritic polymers can be used to improve the solubility of curcumin, and the drug released faster in the presence of CO2. Such CO2 responsive fluorescent dendritic polymers are potentially applicable in cellular imaging or drug controlled release.
研究领域:
材料科学
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生物医学工程
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Mengyuan Zhang,Jian Ye,Nana Lu,Xiaoyan Lu,Kongliang Luo,Jiali Dong,Qiang Niu,Pengfei Zhang,Sheng Dai
CO 2 methanation at low temperatures is still a challenge. Herein, Ni n CeO x (n = 1–3) and Ni 2.5 Pd 0.1 CeO x nanofibers by electrospinning is reported. The main advantage of this method is to obtain the highly dispersed precursor of palladium, nickel, and cerium, overcoming the difficulty of uniform mixing in conventional preparation methods. The Ni 2.5 Pd 0.1 CeO x nanofiber catalyst exhibited outstanding catalytic performance at low temperatures (CO 2 conversion rate = 90.4 %, CH 4 selectivity = 99.6 % at 230 °C) along with exceptional stability over 300 h. EPR, Raman, and O 1s XPS confirmed that Pd 2+ doping increased oxygen vacancy concentration. In-situ infrared spectroscopy indicated that CO 2 methanation on Ni 2.5 CeO x and Ni 2.5 Pd 0.1 CeO x catalysts followed the formate pathways. Pd 2+ doping increased the number of surface oxygen vacancies and hydroxyl groups, thus increasing the amount of bicarbonates and formates. DFT calculations suggested that Pd 2+ doping increased CO 2 adsorption energy, and confirmed surface hydroxyl groups and bicarbonate being beneficial for CO 2 methanation, consequently enhancing the activity of Ni 2.5 Pd 0.1 CeO x catalyst especially at low temperatures.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2021
·
IF 3.247
Wenwen Huang,Jiacheng Liu,Na Rao,Guozhi Fan,Juntao Yan,Qunpeng Cheng,Guangsen Song
Concerning the increasing greenhouse effect, the development of efficient CO2 adsorbents is very important. In this study, the influence of surfactant on the adsorption performance of amine-functionalized MCM-41 was analysed. The results showed that the residual amount of surfactant in MCM-41 was gradually decreased with the increase of calcination temperature which improved the pore structure. The maximum adsorption capacity (5.495 mmol/g) appeared at PEI-MCM-41-100°C indicated that the adsorption capacity could be improved under the function of surfactant. By calculating the diffusion coefficient of CO2 adsorption process in PEI-MCM-41-100/200/300/400/550°C, the diffusion resistance of CO2 was the lowest in PEI-MCM-41-100°C, which directly proved that the synergism of surfactant and organic amine could reduce the diffusion resistance of CO2 in the pore.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Peng Wang,Jian Sun,Yafei Guo,Chuanwen Zhao,Weiling Li,Guodong Wang,Su Lei,Ping Lu
The development of K 2 CO 3 -based sorbents with desirable CO 2 capture capacity and mechanical property is highly necessary for its large-scale application. In this work, a range of extruded-spheronized K 2 CO 3 -based pellets containing different K 2 CO 3 loading (30–70 wt%) and Al 2 O 3 -based supports (i.e., activated alumina, Bayer aluminum hydroxide, kaolinite clay and calcium aluminate cement) were prepared for CO 2 capture. It is found that the distinct textural properties of different supports result in the obvious diversities in CO 2 uptake and mechanical property of K 2 CO 3 -based pellets. The activated alumina-supported sorbent pellets loaded with 50 wt% of K 2 CO 3 possess the highest CO 2 adsorption capacity of 2.29 mmol/g. It is mainly attributed to the moderate amounts of active component contributing to good textural properties and abundant CO 2 -philic sites, whereas excessive K 2 CO 3 loading will cause the destruction of porous structure, consequently the inferior CO 2 uptake. Moreover, the addition of 15 wt% of urea can furher enhace CO 2 uptake of the activated alumina-supported sorbent pellets loaded with 50 wt% of K 2 CO 3 , ∼3.10 mmol CO 2 /g. The improved CO 2 uptake is due to the significantly enhanced porosity of sorbent pellets as a result of urea decomposition. In addition, the urea-templated sorbent pellets still maintain the high compressive strength (18.96 MPa) and good attrition resistance (a weight loss of 0.59% after 4000 rotations).
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Lixin Song,Guobin Liu,Zhenping Qu
CO 2 hydrogenation to methanol and/or dimethyl ether (DME) holds promise for mitigating greenhouse gas effects and addressing energy scarcity. However, the relationship between product selectivity and the collective nature of the catalysts remains ambiguous due to the intricate reaction network. Here, a series of Cu/Zn x Al y O z catalysts with different surface properties have been engineered by manipulating the Zn/Al ratio to achieve product controllability for CO 2 hydrogenation. The results unveil the pivotal role of the H 2 dissociation capability in governing CO 2 conversion, which is regulated by the concentration of Cu 0 species. Furthermore, the number of surface hydroxyl groups, the proportion of moderately strong basic sites and moderately strong acidic sites show desirable linear correlations with the selectivity of CO, CH 3 OH, and DME, respectively. Importantly, the ZnAl 2 O 4 -Al 2 O 3 or Cu-ZnAl 2 O 4 -Al 2 O 3 interface notably enhances moderately strong acidic sites, aiding methanol dehydration to DME. This work offers a comprehensive guide to the rational design of catalysts for oriented product synthesis from CO 2 hydrogenation.
研究领域:
催化化学
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能源化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2024
·
IF 7.5
Rui Yang,Xiaozhong Zheng,Hao Fu,Xinyue Cao,Yangguang Hu,Yiyin Huang
Graphical Cu 7 S 4 /Cu nanoflowers with strong CO 2 adsorption and abundant boundaries were developed by a facile thermal reduction, which underwent in situ dynamic restructuring during ECR to generate highly active S-doped Cu 2 O/Cu hybrid catalyst. Thermodynamic and experimental analysis revealed that the optimized adsorption of the HCOO * intermediate on S−Cu 2 O/Cu was regulated and surface H was suppressed by S-doping. The high activity for CO 2 -to-HCOOH attributed to the strengthen CO 2 adsorption, abundant boundaries at Cu 2 O/Cu interfaces, and the regulation of adsorption energy by S-doping Optimized catalytic properties and reactant adsorption energy played a crucial role in promoting CO 2 electrocatalysis. Herein, Cu 7 S 4 /Cu underwent in situ dynamic restructuring to generate S−Cu 2 O/Cu hybrid catalyst for effective electrochemical CO 2 reduction to formate that outperformed Cu 2 O/Cu and Cu 7 S 4 . Thermodynamic and in situ Raman spectra revealed that the optimized adsorption of the HCOO* intermediate on S−Cu 2 O/Cu was regulated and the H 2 pathway (surface H) was suppressed by S-doping. Meanwhile, Cu 7 S 4 /Cu nanoflowers created abundant boundaries for ECR and strengthened the CO 2 adsorption by inducing Cu. These findings provide a new perspective on synthetic methods for various electrocatalytic reduction processes.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 8
·7950-7962
·
IF 2.195
Hu Bingbing,Guo Qiang,Wang Kang,Wang Xitao
In this paper, a series of indium oxides were prepared by calcining the In(OH) 3 precursors, which were synthesized by hydrothermal method using the mixed solution of ethylenediamine (En) and water as a solvent. The morphologies, particle sizes, pore structure, crystallinity and surface defect concentration of these photocatalysts were adjusted by varying the ratio of En to water during the preparation of In(OH) 3 precursors. The results revealed that In 2 O 3 photocatalysts obtained from the precursor prepared in En containing solvent exhibited much higher photocatalytic activities for CO 2 reduction with H 2 O when compared to that derived from the precursor prepared in pure water. This result can be ascribed to several reasons as following. Firstly, the En addition with a suitable amount can improve the crystallinity of In 2 O 3 and decrease the surface defect concentration, which obviously depressed the recombination of photogenerated electrons and holes. Also, the addition of En during the preparation of precursor can decrease the particle size, increase specific surface area and pore structure, resulting into the increase of active sites. Finally, the band gap of In 2 O 3 can be slightly narrowed after the addition of En, resulting in enhanced light absorption in the visible region. When the ratio of ethylenediamine to water is 1:1, the as-prepared In 2 O 3 possessing the largest specific surface area and pore volume, enhanced light absorption ability and higher hole–electron separation efficiency, exhibited the highest photocatalytic activity. Under visible light irradiation, the H 2 , CO and CH 4 production rates of 5.3, 8.3 and 27.2 µmol/g cat /h can be achieved, respectively.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2025
·
IF 7.4
Huang Fuxia,Liu Yifei,Wang Feng,Liu Ya,Guo Liejin
BiOI materials show significant potential for photocatalytic CO 2 reduction, but their limited CO 2 activation and poor charge carrier properties hinder conversion efficiency. In this study, we engineered BiOI-based photocatalysts with abundant crystal defects to enhance performance. X-ray diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM) revealed lattice distortions and twin crystals in BiOI-LD and BiOI-TC. Ultraviolet-visible spectroscopy, micropore and chemisorption analyses, and photoluminescence spectroscopy demonstrated that crystal defects improved light absorption, CO 2 adsorption, charge transfer efficiency, and carrier lifetime. Electron paramagnetic resonance (EPR) spectroscopy showed increased superoxide radical generation in BiOI-TC, suggesting higher reactivity. Consequently, BiOI achieved a CH 3 CH 2 OH generation rate of 6.2 µmol g −1 h −1 with 100% selectivity. Key intermediates (*CO, *COCO, *CHO, *CH 2 ) for CH 3 CH 2 OH production were identified, and C 2 H 6 formation in BiOI-LD was linked to the generation of *CH 3 .
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2019
·
IF 3.073
Suresh Mutyala,Madhavi Jonnalagadda,Harisekhar Mitta,Raveendra Gundeboyina
MIL-101 (Cr) was synthesized by a hydrothermal method and used as support to prepare a series of polyethylenimine (PEI) incorporated MIL-101 (Cr) by wet impregnation method. All characterization results revealed that the structure of MIL-101 (Cr) was well-maintained by the incorporation of polyethylenimine and confirmed the presence of PEI within MIL-101 (Cr). The CO 2 adsorption studies were carried out in a fixed bed reactor from 30 to 90 °C, 1 bar. The adsorption of CO 2 has been increased by the incorporation of PEI. It was due to the chemical interaction between the NH 2 and CO 2 groups to form a carbamate. The high CO 2 adsorption capacity 3.81 mmol g −1 was shown by 70 wt% PEI loaded MIL-101 (Cr) at 75 °C, 1 bar, because of more number of NH 2 groups and a high number of CO 2 molecules diffusion. Its adsorption capacity was 4.7 times higher than the adsorption capacity of MIL-101 (Cr) (0.80 mmol g −1 ). Moreover, in moisture condition, CO 2 adsorption capacity was increased to 4.4 mmol g −1 by the formation of ammonium bicarbonate and showed good adsorption stability throughout each adsorption-desorption cycle. The Avrami adsorption kinetic model was well fitted with experimental breakthrough CO 2 adsorption data of MIL-101 (Cr)-PEI-70. It suggested that the adsorption of CO 2 on PEI incorporated material was chemical adsorption.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Carbon Letters
·
2023
·Vol. 33
·期 5
·1395-1406
·
IF 4.5
Chen Zhangjing,Li Liangliang,Cheng Gang
Photocatalytic CO 2 reduction is a promising approach for reducing CO 2 emissions and achieving the goal of carbon neutrality. In this work, selectively coupling Cu(OH) 2 and CuO with amine-modified brookite TiO 2 (NH 2 –B–TiO 2 ) has been achieved by a simple precipitation method. The results show that CuO is better than Cu(OH) 2 as a co-catalyst to enhance the CO 2 photoreduction capability of NH 2 –B–TiO 2 . The highest rates of CO 2 conversion to CH 4 and CO of NH 2 –B–TiO 2 –CuO composite reach 6.05 and 3.25 μmol h −1 g −1 , respectively, which is higher than 8 times the yield of CH 4 of NH 2 –B–TiO 2 . It is proposed that the NH 2 –B–TiO 2 –CuO composite offers an effective charge transfer through the formation of a p–n junction between NH 2 –B–TiO 2 and CuO interfaces, while in the NH 2 –B–TiO 2 –Cu(OH) 2 composite, the Cu(OH) 2 dominantly serves as an electron sink to capture photo-induced electrons, promoting photo-induced carrier separation. This work provides an ingenious synthetic method for selectively anchoring Cu(OH) 2 and CuO on semiconductors with different charge transfer routes for an efficient CO 2 photoreduction. Graphical abstract
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）