Journal of CO2 Utilization
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2017
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IF 4.292
Chen Zhang,Haiyan Yang,Peng Gao,He Zhu,Liangshu Zhong,Hui Wang,Wei Wei,Yuhan Sun
A series of Cu/ZnO/Al 2 O 3 catalysts with the total weight percentage of Cu and ZnO from 9.94 wt.% to 44.5 wt.% have been prepared by ammonia deposition −precipitation method and tested for methanol synthesis from CO 2 hydrogenation. A Cu/Zn/Al layered double hydroxides (LDHs) precursor can be formed in situ on the surface of microspherical Al 2 O 3 which acts as both support and sole source of Al 3+ cations. With increase of total Cu and ZnO loading, the dispersion of copper and reducibility of CuO decline continuously, while the exposed copper surface area increases gradually. In addition, the formation of LDHs results in a stronger both basicity and acid strength on the catalyst surface. It is found that the CO 2 conversion increases linearly with increase of the Cu and ZnO loading. The methanol selectivity for the catalyst with low total metal loading (9.94 wt.%) is much lower than those for other catalysts, though it increases with increasing loading, which can be mainly assigned to the much smaller Cu particle size (<5 nm) and the higher ratio of isolated CuO phase. Moreover, the Cu/ZnO/Al 2 O 3 catalyst with relatively high total metal loading (44.50 wt.%) still exhibits a considerable stable catalytic performance due to the formation of LDH structure.
研究领域:
催化
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化学工程
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材料科学
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环境化学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Lei Li,Guolan Wei,Hengji Liu,Yongde Guo,Yingying Ma
Traditional nanofiber-hybrid proton exchange membranes (PEMs) are limited in their further application due to differences in proton conductivity between vertical and horizontal orientations. In this study, we design and synthesize a novel type aminated flower-shaped ZnO@Al 2 O 3 nanofibers and then filling its three-dimensional interstices with sulfonated polysulfone (SPSF) to obtain a nanofiber composite proton exchange membrane (ZANFs/SPSF). The Al 2 O 3 nanofibers provide long-range and stable proton transport nanochannels in plane, while the flower-shaped ZnO on its surface provide additional vertical transport channels for protons. This combination of 1D and 2D conductive pathways forms a typical 3D hierarchical proton conductive configuration, optimizing the proton transfer pathway. Specifically, the amino groups (-N-H) on the nanofibers surface not only form acid-base pairs with sulfonic acid groups (-SO 3 H), providing a rich hydrogen bonding network for proton hopping, but also have a similar structure to the polyether sulfone groups (–SO 2 –NH-), which significantly improves the compatibility between the nanofibers and SPSF. Additionally, the flower-like pleated surface of the nanofibers has a high contact area with the SPSF, providing more proton hopping sites, improving the utilization efficiency of proton carriers, and also resulting in a more stable structure. Moreover, the crosslinked network of nanofibers serves as a barrier to further inhibit methanol permeation. The ZANFs/SPSF exhibits excellent parallel proton conductivity of 348 mS cm −1 at 80 °C and 100% RH, which is 2.7 times higher than that of SPSF under the same conditions, and achieves a peak power density of 405.7 mW cm −2 . This approach presents a unique perspective for the preparation of high-performance PEMs for methanol fuel cells.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 8
·2343-2352
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IF 5.721
Ziheng Zhen,Wenxiang Tang,Wei (Willy) Chu,Tao Zhang,Li Lv,Shengwei Tang
The dispersity and the neighboring degree of different sites play crucial roles in the catalytic performance of dual site catalysts. The solution of precursors was encapsulated into microdroplets by forming a microemulsion. The average diameter of microdroplets was about 45 nm. This guaranteed that the dosage of precursors was at the attogram level and only about a thousand precursor molecules were encapsulated in each microdroplet. An anti-solvent extraction method was applied to extract water from the microdroplets with acetonitrile. The precursors co-precipitated in the microdroplets due to the loss of water. The encapsulated precursors in the microdroplets co-precipitated together in nanoscale space, so the neighboring degree of the two precursors was improved significantly. The prepared catalyst was characterized by ICP-OES, BET, XRD, H2-TPR, TEM and XPS. Compared with the Cu–ZnO/Al2O3 (CZA) catalysts prepared by the conventional impregnation method, the CZA catalysts prepared by the proposed strategy had much stronger interaction and a better neighboring degree of the dual active sites. They also showed very good catalytic performance for the reverse water gas shift (RWGS) reaction. The CO2 conversion of the designed CZA catalysts was about 1–2 times higher than that of the CZA catalysts prepared by the conventional impregnation method at 0.1 MPa, 300–400 °C and a CO2/H2 mole ratio of 1.
研究领域:
催化化学
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材料科学
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环境工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Lan li,Jie Sun,Hao Ling,Feng Ju
NiSO4/ZnO-Al2O3-SiO2 adsorbent, as a novel reactive adsorption desulfurization (RADS)adsorbent, has self-sulfidation ability and high desulfurization performance when treating model fuel. However, the RADS performance of the adsorbent under FCC gasoline feedstock is not well understood. Here, we compare the performance of the adsorbent under FCC gasoline with model fuel to test the effect of the hydrocarbon composition of the feedstock. The complex composition of FCC gasoline makes it sensitive to the nickel loading amount of the adsorbent. Under the influence of specific surface area and pore structure, the adsorbent loaded with 3 wt% nickel shows better desulfurization activity when treating FCC gasoline. As hydrocarbons in FCC gasoline compete with sulfur compounds for active Ni sites, the reaction conditions have been tested and optimized to achieve deep desulfurization while maintaining low olefin loss to ensure the octane number of the product. By experimental tests and characterization, it has been proved that NiSx and NiO acted as active Ni sites of the adsorbent. Based on these observations, the mechanism of RADS of FCC gasoline over NiSO4/ZnO-Al2O3-SiO2 adsorbent has been proposed, which provides theoretical support for the development of new adsorbents and the optimization of RADS process.
研究领域:
化学工程
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环境科学
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石油炼制
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2023
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IF 9.5
Wenda Bao,Yue Zhang,Rongliang Shang,Fufei Cong,Haojie Zhao,Yuqing Zuo,Beili Yi,Jin Xie
Vapor phase infiltration (VPI) derived from atomic layer deposition (ALD) enables inorganic materials to nucleate and grow within the free volume of polymers, which has shown promising prospects in the field of composite solid polymer electrolytes (CSPEs). However, there are only a few types of metal oxides that can be incorporated into the polymer matrix by VPI, let alone binary metal oxides, due to the limited knowledge of the VPI synthesis process. To combine the merits of different metal oxides, we investigate the VPI method to prepare ZnO-Al2O3 composites in poly(ethylene oxide) (PEO). When the introducing order is Al2O3/ZnO (AZO), due to the extremely high reactivity of trimethyl aluminum (TMA) with PEO, VPI-Al2O3 will accumulate near the surface of PEO. The surface Al2O3 layer inhibits the further diffusion of the diethyl zinc (DEZ) into the PEO matrix, leading to weak polymer–filler interactions and limited improvement of the Li+ conduction. In the incorporation order of ZnO/Al2O3 (ZAO), the moderate reactivity of DEZ renders the uniform distribution of VPI-ZnO within PEO, and the following TMA can both react with PEO and VPI-ZnO particles near the surface of PEO, which not only preserves the interactions between VPI-ZnO and PEO but also better inhibits the growth of lithium dendrites. The incorporation order plays a crucial role in the morphology and composition of binary metal oxides synthesized by VPI.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2026
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IF 7.3
Wenjun Zhang,Zijiang Zhao,Yonggang Gang,Xiaosong An,Liboting Gao,Siyi Bao,Xuping Ren,Jun Wang,Jianhua Yan,Hao Zhang
Cu/ZnO/Al2O3 (CZA) catalyst remains the benchmark for methanol synthesis but suffers from active-site sintering and insufficient CO2 activation. In this study, we proposed a dual strategy to enhance and regulate the active sites of CZA: hydrothermal treatment induces Cu–Zn coordination to create high-density Cu–ZnO1–x interfaces that promote CO2 conversion, while subsequent La doping regulates Cu0/Cu+ species to favor methanol selectivity. As a result, the maximum space-time yield (STY) of methanol over the designed CZA&5%La-LRCP (prepared by the ligand-regulated coprecipitation method) catalyst improved significantly from 283.0 gMeOH·kgcat–1·h–1 for the conventional coprecipitation-prepared CZA to 400.4 gMeOH·kgcat–1·h–1 under the tested conditions, surpassing most literature reports on La-doped Cu-based catalysts. Comprehensive characterizations and kinetic studies revealed that high-density Cu–ZnO1–x interfaces enhance CO2 adsorption and activation, while uniformly distributed electron-enriched Cu0/Cu+ species promote H2 dissociation and facilitate formate formation and transformation, together establishing an efficient pathway for CO2 activation and hydrogenation. This study demonstrates a promising strategy for the rational design of CO2hydrogenation catalysts through the synergistic modulation of interfacial structure and electronic properties.
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DOI
高影响因子
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