MACROMOLECULES
·
2015
·
IF 5.8
Zefeng Song,Ke Wang,Chengqiang Gao,Shuang Wang,Wangqing Zhang
A new multi-stimuli-responsive homopolymer of poly[N-[2-(diethylamino)ethyl]acrylamide] (PDEAEAM), which combines the thermoresponsive and pH/CO2-responsive moieties of the diethylamino and acrylamide groups, was proposed and synthesized by RAFT polymerization. Well-defined PDEAEAM was synthesized by solution RAFT polymerization as indicated by the linear increase in the polymer molecular weight with the monomer conversion and the narrow molecular weight distribution. The appending diethylamino group in the polymer backbone was found to be crucial to determine the thermoresponse of PDEAEAM in water. The parameters including the polymerization degree, the polymer concentration, the deuterated solvent, the terminal attached on the polymer backbone, the additives of salt and urea, and pH and bubbling CO2 affecting the thermoresponse of PDEAEAM in aqueous solution at the lower critical solution temperature (LCST) were investigated. The temperature-variable 1H NMR analysis suggests that the dehydration of PDEAEAM at temperature above LCST is ascribed to the weakened hydrogen bonding between the CONHCH2 and/or (CH2N(CH2CH3)2) moieties with the solvent of water. The proposed multi-stimuli-responsive homopolymer of PDEAEAM has two advantages of (1) the convenient and controllable RAFT synthesis and (2) the pH/CO2 tunable LCST at ∼36 °C being very close to body temperature.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Xiaoqian Zhang,Chengli Jiao,Xinxin Li,Xiangju Song,Tatiana V. Plisko,Alexandr V. Bildyukevich,Heqing Jiang
Polyamide membrane, fabricated via interfacial polymerization process, is a typical class of facilitated transport membrane for CO 2 separation with amino groups serving as reactive CO 2 carriers. Herein, to further enhance the CO 2 -facilitated transport effect of polyamide membrane, Zn(NO 3 ) 2 is directly introduced into aqueous triethylenetetramine phase for constructing Zn-N coordination polyamide membrane taking advantage of the coordination interaction between Zn ions and amino groups from triethylenetetramine. The good solubility of Zn(NO 3 ) 2 in aqueous amine solution and moderate coordinative ability of Zn ions are beneficial to a uniform distribution of Zn in polyamide layer. The coordination of N from triethylenetetramine monomer to Zn ion centre produces more tertiary amino groups and free amino groups with stronger affinity to CO 2 in Zn-N coordination membrane for enhancing the facilitated transport effect. Additionally, the Zn-N coordination interaction generates smoother surface of membranes when sufficient Zn ions are introduced. The membrane with 0.1 wt% of Zn ions in aqueous phase exhibits the highest CO 2 /N 2 and CO 2 /CH 4 selectivity of 106.7 and 55.2, which increase, respectively, by 75.2% and 99.3% without compromising CO 2 permeance in contrast with pristine polyamide membrane.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Zhi-Wen Wang,Qiang Wan,Ying-Zhang Shi,Huan Wang,Yue-Yue Kang,Shu-Ying Zhu,Sen Lin,Ling Wu
Ultrathin TiO 2 nanosheet (NST) with abundant Ti 3+ sites is developed as a photocatalyst which exhibits a high yield (147.2 μmol g −1 h −1 ) and selectivity (96.8%) for CO 2 to CH 4 . The results of in situ FTIR, in situ EPR and density functional theory (DFT) calculation suggest that CO 2 would be selectively activated on NST surface via forming the bridging Ti···CO 2 − ···Ti coordination species which not only lowers the activation energy barrier, but also determines the selectivity of CH 4 . Additionally, NST with the better separation and transfer ability for photogenerated electrons-holes can fleetly supply the electrons to CO 2 molecules for high efficiently producing CH 4 via the Ti-C coordination bond. Finally, a possible mechanism of the synergistic effect about coordination-activation and photocatalysis is discussed at a molecule level. This work would offer a perspective for designing an effective photocatalyst and tailoring the selectivity of products by coordination activation.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Yunqi Zhou,Ye Yuan,Xinlei Liu,Zhi Wang
Metal-organic framework (MOF) membranes with proper pore size distribution and functional groups are generally more suitable for separation. Most MOFs are characterized by a hierarchical pore structure, which possesses large cavities surrounded by small windows. Fabrication of MOF membranes only retaining microporous fragment structure is a workable method to narrow pore size distribution. In this study, well-grown NH 2 -MIL-101(Cr) fragment membranes were fabricated for CO 2 separation by adjusting acetic acid – ligand – metal ratio to balance the nucleation and growth. NH 2 -MIL-101(Cr) fragment has a similar chemical structure to NH 2 -MIL-101(Cr) as expected, but only small pores with size around 0.56 nm is retained. The NH 2 -MIL-101(Cr) fragment membranes exhibited CO 2 /N 2 selectivity of about 37 with CO 2 permeance up to 6104 GPU.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2022
·Vol. 9
·期 16
·2105292
·
IF 17.521
Yawen Jiang,Xinyu Wang,Delong Duan,Chaohua He,Jun Ma,Wenqing Zhang,Hengjie Liu,Ran Long,Zibiao Li,Tingting Kong,Xian Jun Loh,Li Song,Enyi Ye,Yujie Xiong
Structural reconstruction is a process commonly observed for Cu-based catalysts in electrochemical CO 2 reduction. The Cu-based precatalysts with structural complexity often undergo sophisticated structural reconstruction processes, which may offer opportunities for enhancing the electrosynthesis of multicarbon products (C 2+ products) but remain largely uncertain due to various new structural features possibly arising during the processes. In this work, the Cu 2 O superparticles with an assembly structure are demonstrated to undergo complicated structure evolution under electrochemical reduction condition, enabling highly selective CO 2 -to-C 2+ products conversion in electrocatalysis. As revealed by electron microscopic characterization together with in situ X-ray absorption spectroscopy and Raman spectroscopy, the building blocks inside the superparticle fuse to generate numerous grain boundaries while those in the outer shell detach to form nanogap structures that can efficiently confine OH − to induce high local pH. Such a combination of unique structural features with local reaction environment offers two important factors for facilitating C−C coupling. Consequently, the Cu 2 O superparticle-derived catalyst achieves high faradaic efficiencies of 53.2% for C 2 H 4 and 74.2% for C 2+ products, surpassing the performance of geometrically simpler Cu 2 O cube-derived catalyst and most reported Cu electrocatalysts under comparable conditions. This work provides insights for rationally designing highly selective CO 2 reduction electrocatalysts by controlling structural reconstruction.
研究领域:
材料科学
·
电化学
·
环境科学
✓ 已验证
DOI
高影响因子
Reaction Chemistry & Engineering
·
2024
·Vol. 10
·期 1
·203-213
·
IF 3.4
Ning Ma,Liu Yang,Zhenchang Fang,Kaijia Jiang,Xinling Li,Zhen Huang
Deficiencies such as high viscosity, volatility, and rich phase precipitation limited the engineering application of non-aqueous absorbents. A series of high boiling point solvent screening experiments were conducted to develop an absorption saturated solution with a homogeneous phase at low viscosity (14.71 mPa s) in this study. Further addition of polyamines increased the absorption capacity by 42% (3.55 mol CO2 per kg). The 13C NMR results indicated that in the DETA/MEA/NMF blended amine system, MEA was involved in the deprotonation process of DETA zwitterions as proton acceptors. Quantum chemical calculations were utilized to compare the energies of each possible single-step reaction, providing insights into the reaction pathways of the blended amine system. The rate constant of the MEA/CO2 reaction was found to be 1.98 times that of the DETA/CO2 reaction, indicating lower reaction activity, consistent with NMR results. In addition, the results of the analysis of weak interactions revealed that the hydrogen bonds were key factors affecting the viscosity change and precipitation in non-aqueous absorbents, providing a new method for designing novel low-viscosity non-aqueous absorbents. The combination of theoretical analysis and experimental results underscores the potential of the blended amine non-aqueous absorbent as a feasible alternative for the industrial applications of CO2 capture.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
·
2024
·
IF 7.2
Luqman Abdullahi Sani,Haolong Bai,Zifu Xu,Liangliang Fu,Yining Sun,Xiaorui Huang,He Gao,Xuejing Liu,Dingrong Bai,Zhanguo Zhang,Fabing Su,Jiao Liu,Guangwen Xu
Ni/Al 2 O 3 catalysts (noted as Ni/Al-350, Ni/Al-500, and Ni/Al-700, respectively) were synthesized by a facile solution combustion method but at different combustion temperatures (350 °C, 500 °C, and 700 °C, respectively). For comparison, Ni/Al 2 O 3 (noted as Ni/Al-100) was also prepared by the impregnation method and applied in the methanation reaction. The Ni/Al 2 O 3 synthesized at the combustion temperature of 350 °C showed better performance than the others at higher combustion temperatures, and the activity for CO 2 methanation followed an order of Ni/Al-350 > Ni/Al-500 > Ni/Al-700 > Ni/Al-100. The increase in the combustion temperature decreased active sites for the H 2 and CO 2 adsorption, which could be associated with the reduced Ni dispersion and basic sites, thus lowering its activity and increasing its carbon deposition rate.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2016
·Vol. 32
·期 3
·605-610
·
IF 0.844
CHEN Feng-Feng,DONG Yan,SANG Xiao-Yan,ZHOU Yan,TAO Duan-Jian
Four tetrabutylphosphonium carboxylate ionic liquids ([P4444][CA]) were prepared, and their densities, viscosities, refractive indices, and conductivities were measured and correlated with thermodynamic and empirical equations in the temperature range of 298.15-348.15 K.
The influence of temperature on these four properties of [P4444][CA] was discussed, and their thermal expansion coefficient values were calculated. The CO2 absorption capacity of [P4444][CA] was studied at 313.15 K and 100 kPa. The results indicated that [P4444][Buty]
had the highest CO2 capture capacity among these ionic liquids, with an absorption capacity of 0.4 mol·mol-1 and balance time of less than 5 min.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Di Li,Qin Li,Yimeng Zhou,Qiong Zhang,Qianjin Ye,Ran Yang,Deli Jiang
Steering selectivity in photocatalytic conversion of CO2, especially toward deep reduction products, is vital to energy and environmental goals yet remains a great challenge. In this work, we demonstrate a facet-dependent photocatalytic selective reduction of CO2 to CH4 in Cu-doped TiO2 catalysts exposed with different facets synthesized by a topological transformation from MIL-125 (Ti) precursors. The optimized round cake-like Cu/TiO2 photocatalyst mainly exposed with the (001) facet exhibited a high photocatalytic CO2 reduction performance with a CH4 yield of 40.36 μmol g–1 h–1 with a selectivity of 94.1%, which are significantly higher than those of TiO2 (001) (4.70 μmol g–1 h–1 and 52.6%, respectively), Cu/TiO2 (001 + 101) (18.95 μmol g–1 h–1 and 69.6%, respectively), and Cu/TiO2 (101) (14.73 μmol g–1 h–1 and 78.9%, respectively). The results of experimental and theoretical calculations demonstrate that the Cu doping dominating the promoted separation and migration efficiencies of photogenerated charges and the preferential adsorption on (001) facets synergistically contribute to the selective reduction of CO2 to CH4. This work highlights the significance of synergy between facet engineering and ion doping in the design of high-performance photocatalysts with respect to selective reduction of CO2 to multielectron products.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 11
·1-17
·
IF 2.8
Pan Deng,Wang Yanan,Lin Liwei,Zhang Yuzhe,Zhou Man,Li Zhongyu,Xu Song
Photothermal catalytic CO 2 reduction can combine photocatalysis and thermal catalysis by using full-spectrum solar energy to convert CO 2 into high value-added chemicals. This can effectively alleviate the problems of excessive CO 2 emissions and thermal catalytic energy waste. In this paper, a novel catalyst was prepared using Ce-MOF as a precursor to generate Cu/Ni/CeO 2 for efficient reduction of CO 2 to CO by hydrogenation. Due to the rod-like structure of CeO 2 and the high dispersion of Cu and Ni nanoparticles, 10%Cu 5%Ni CeO 2 can achieve a catalytic activity of 54.21 mmol g −1 h −1 in the full solar spectrum. The supported Cu and Ni metals are the active sites for catalytic reduction. Meanwhile, Cu and Ni enhanced the light absorption ability of the catalyst and the surface temperature under illumination. This is due to the hot charge carriers generated by LSPR effect in Ni and Cu metal nanoparticles, which can dissipate energy through local heating, thus increasing the temperature of the catalyst under illumination. It can be found that the CO 2 reduction activity of photo-assisted thermocatalysis is higher than that of thermal catalysis under the same conditions. Therefore, the combined effect of the electrons generated by UV–Vis light and the heating effect of near-infrared light on catalyst could improve the catalytic activity. This work might provide a potential strategy for efficient photothermal reduction of CO 2 in the future.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
VACUUM
·
2024
·
IF 3.8
Kaiting Yang,Xiongtao Lv,Jingwen Meng,Huiqing Wang,Lin Guo,Xin Li,Fengyun Su,Qing Lan,Zhengdao Li,Wei Wang,Yuwei Guo,Xiaoli Jin,Haiquan Xie
Photothermal catalytic reduction of CO 2 into high value-added C 2 hydrocarbon products is a promising method for efficient CO 2 conversion. However, current photocatalysts still encounter obstacles including limited photoabsorption range, rapid recombination of photogenerated carriers , and inadequate surface active sites. Herein, Bi 4 O 5 Br 2 co-modified with oxygen vacancy (OV) and metal bismuth (Bi) (Bi 4 O 5 Br 2 -OV@Bi) has been prepared to optimize these crucial issues. Bi 4 O 5 Br 2 -OV@Bi delivers a remarkably improvement in CO 2 photothermal conversion, reflecting by the notable increase in C 1 (CO and CH 4 ) and newly generated C 2 (C 2 H 4 and C 2 H 6 ) products compared to pristine Bi 4 O 5 Br 2 . In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectrometry reveals that OC−COH* intermediate promotes the C–C coupling for produce C 2 hydrocarbons. This study strengthens the understanding of metal modification and defect engineering for forming C 2 hydrocarbons on bismuth-based photocatalysts .
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Xianying Wang,Yingshu Wang,Meichao Gao,Jinni Shen,Xipeng Pu,Zizhong Zhang,Huaxiang Lin,Xuxu Wang
Construction of composite semiconductors is an effective solution to elevate the efficiency of photocatalysis by prolonging lifetime of photogenerated hole and electrons. Herein, a heterojunction structure composite BiVO 4 /Bi 4 Ti 3 O 12 was synthesized via a facile in situ hydrothermal condition. The novel composite photocatalyst has excellent photocatalytic ability to reduce CO 2 with H 2 O into CH 3 OH and CO. The BiVO 4 /10 % Bi 4 Ti 3 O 12 sample shows the highest yields of CH 3 OH and CO up to 16.6 and 13.29 μmol g −1 h −1 , which was 12.39 and 5.68 times higher than that of pure BiVO 4 , and 9.88 and 2.80 times higher than that of pure Bi 4 Ti 3 O 12 , respectively. Such a high activity is attributed to the type II heterojunction structure which significantly enhances separation of photogenerated carriers and promotes collaboration between the water oxidation on the Bi 4 Ti 3 O 12 and the CO 2 reduction on BiVO 4 . The photocatalytic reaction mechanism of CO 2 on the composite was proposed according to experiment results.
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