CATALYSIS LETTERS
·
2019
·Vol. 150
·期 4
·1121-1127
·
IF 2.372
Xu Siquan,Wu Ningxin,Yuan Hui,Chen Yuan,Pan Donghui,Wu Yuanfeng,Fan Jingdeng,Gao Lijing,Xiao Guomin
Abstract Silica-supported hafinum phosphide (HfP/SiO 2 ) was prepared and applied as an effective solid acid catalyst to drive furfural production from xylan. Various characterizations were employed to analyze the intrinsic properties of the HfP/SiO 2 catalyst, and the effects of process parameters on its performance were investigated in detail. The results showed that the performance of the HfP/SiO 2 catalyst was excellent, which allowed up to 85% of the furfural yield to be achieved at 180 °C for 60 min in the water (NaCl) /THF biphasic system. There was no significant decrease in the performance of the HfP/SiO 2 catalyst after seven consecutive cycles. Characterization analysis of the recovered catalyst revealed that its elemental composition and total acidity were maintained, indicating the desired hydrothermal stability of the HfP/SiO 2 catalyst. In addition, by-products produced during xylan conversion were identified as humins and soluble molecular fragments or polymers. Graphic Abstract
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2015
·
IF 3.562
Linjun Shao,Yuan Ren,Zining Wang,Chenze Qi,Yao Lin
Using electrospinning technique to prepare chitosan (CS) nanofibers from an inexpensive solvent such as acetic acid has been a challenge, due to the lack of sufficient entanglements in these semi-rigid polyelectrolytes . Incorporating polymers such as poly(methacrylic acid) (PMAA) into the solution lowers the entanglement concentration of the polymers, and make all three morphology regimes (polymer droplets, beaded nanofibers and nanofibers with uniform thickness) accessible to electrospinning method. Uniform composite nanofibers are found at concentrations well above the entanglement concentration. The thickness and morphology of nanofibers can be regulated by addition of small amount of organic solvents such as dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The composite nanofibers are subsequently crosslinked at an elevated temperature to improve their thermal and solvent stability. The mechanical properties of the crosslinked CS/PMAA fibers can be modulated by varying the amount and molecular weight of PMAA incorporated in the blend. The composite fiber materials provide a useful platform to support a variety of catalysts. As a demonstration, palladium catalyst has been immobilized on the crosslinked CS/PMAA nanofibers to carry out Mizoroki–Heck cross-coupling reactions of aromatic halides and acrylates . We found remarkable catalytic efficiency and stability in these materials. We also demonstrate that, by the “post-modification” of the nanofibers with ligands that chelate metal catalysts , a variety of metal catalysts can be incorporated into the fiber platform, with further improved stability and activity.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2016
·Vol. 26
·期 27
·4839-4847
·
IF 11.382
Yuanyuan Wu,Guo-Dong Li,Yipu Liu,Lan Yang,Xinran Lian,Tewodros Asefa,Xiaoxin Zou
Making highly efficient catalysts for an overall water splitting reaction is vitally important to bring solar/electrical-to-hydrogen energy conversion processes into reality. Herein, the synthesis of ultrathin nanosheet-based, hollow MoO x /Ni 3 S 2 composite microsphere catalysts on nickel foam, using ammonium molybdate as a precursor and the triblock copolymer pluronic P123 as a structure-directing agent is reported. It is also shown that the resulting materials can serve as bifunctional, non-noble metal electrocatalysts with high activity and stability for the hydrogen evolution reaction (HER) as well as the oxygen evolution reaction (OER). Thanks to their unique structural features, the materials give an impressive water-splitting current density of 10 mA cm −2 at ≈1.45 V with remarkable durability for >100 h when used as catalysts both at the cathode and the anode sides of an alkaline electrolyzer. This performance for an overall water splitting reaction is better than even those obtained with an electrolyzer consisting of noble metal -based Pt/C and IrO x /C catalytic couple—the benchmark catalysts for HER and OER, respectively.
研究领域:
材料科学
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化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Lungang Chen,Yong Liu,Canshuo Gu,Gang Feng,Xinghua Zhang,Jianguo Liu,Qi Zhang,Chenguang Wang,Longlong Ma
Selective production of 2-butanol from levulinic acid (LA) hydrogenolysis over a non-precious catalyst is long desirable. However, the process requires the precious metal Ru, and the yield of 2-butanol was less than 65%. Herein, we prepared Ni-based bimetallic catalysts, among which the NiMn catalyst exhibited the highest efficiency and reached an 84.5% yield of 2-butanol at 100% LA conversion under optimal conditions. The electronic states and surface properties were characterized by various techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed desorption, temperature-programmed reduction, and scanning electron microscopy/transmission electron microscopy. The high efficiency of the NiMn catalyst was due to the synergy between Ni0 and Mn2+ species, and the modified surface showed a high basicity and a high affinity to adsorb LA and LA-derived molecules with C═O or COOH. The high affinity of the NiMn catalyst was further confirmed by density functional theory calculations.
研究领域:
催化化学
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可再生能源
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY CONVERSION AND MANAGEMENT
·
2021
·
IF 9.709
Wen Tang,Jing-Pei Cao,Zhi-Hao Wang,Zi-Meng He,Tian-Long Liu,Ze-Ying Wang,Fei-Long Yang,Jie Ren,Xiao-Yan Zhao,Xiao-Bo Feng,Hong-Cun Bai
The development of cheap and highly dispersed nano-catalyst is one of the key technologies for low temperature steam reforming (SR) of biomass tar. This work used acid-washed and oxidized Shengli lignite char (OXAWSL) as carbon precursor to load Co (Co/OXAWSL) and Ni (Ni/OXAWSL) via ion exchange method to SR of toluene and biomass tar. The Co/OXAWSL was more active and stable than Ni/OXAWSL during the 30 h test with a final toluene conversion of 85% at a relatively low temperature of 450 °C and steam to carbon ratio (S/C) of 3.4, which resulted from its small particle size (5.6 nm) and high dispersion (12.3%) of Co. The relatively high H 2 production (42.59 mmol/g-biomass) over Co 0.1 /OXAWSL (450 °C, S/C = 3.4) in SR of tar was also obtained. A low E a (22.0 kJ/mol) value of Co/OXAWSL and good affinity to oxygen for Co explained its excellent performance. The low-temperature tar cracking process can provide theoretical and technical support for the large-scale industrial utilization of biomass pyrolysis and gasification.
研究领域:
能源科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 12
·期 1
·602-610
·
IF 3.361
Yingxin Liu,Kai Liu,Meihua Zhang,Kaiyue Zhang,Jiao Ma,Shuwen Xiao,Zuojun Wei,Shuguang Deng
Highly active and thermally stable Cu–Re bimetallic catalysts supported on TiO2 with 2.0 wt% loading of Cu were prepared via an incipient wetness impregnation method and were applied for liquid phase selective hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) in H2. The effect of the molar ratios of Cu : Re on the physico-chemical properties and the catalytic performance of the Cu–Re/TiO2 catalysts was investigated. Moreover, the influence of various reaction parameters on the hydrogenation of LA to GVL was studied. The results showed that the Cu–Re/TiO2 catalyst with a 1 : 1 molar ratio of Cu to Re (Cu–Re(1 : 1)/TiO2) exhibited the highest performance for the reaction. Complete conversion of LA with a 100% yield of GVL was achieved in 1,4-dioxane solvent under the reaction conditions of 180 °C, 4.0 MPa H2 for 4 h, and the catalyst could be reused at least 6 times with only a slight loss of activity. Combined with the characterization results, the high performance of the catalyst was mainly attributed to the well-dispersed Cu–Re nanoparticles with a very fine average size (ca. 0.69 nm) and the co-presence of Cu–Re bimetal and ReOx on the catalyst surface.
研究领域:
催化化学
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可再生能源
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of CO2 Utilization
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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
·
材料科学
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Yong Yan,Chenyang Zhang,Xin Deng,Jin Zhang,Yali Xue,Jie Zhang,Yingjian Luo,Fuwen Yang,Gang Wang,Ruilin Wang,Jinwei Chen
Water electrolysis is an environmentally friendly and sustainable hydrogen production method. The proper design of the catalyst surface is essential for the oxygen evolution reaction (OER) in the water electrolysis process because the catalytic effect is highly dependent on contact surface properties such as the homogeneity of the coating and the stability of the catalyst, as well as the wettability of the electrolyte. Herein, hydrogel [consisting of poly(vinyl alcohol) (PVA) cross-linked with quaternized chitosan (HACC)] loaded on nickel foam (NF) was chosen to study the OER properties of iron (Fe) in organic molecules. Owing to the unique hydrophilicity, uniformity, and stability of hydrogel, the superhydrophilic Fe-HACC-PVA/NF exhibits a low overpotential of 225 mV versus reversible hydrogen electrode at 10 mA cm–2 and shows favorable stability (only 2.3% loss of current density after 24 h at 100 mA cm–2), which outperforms most Fe-based transition-metal OER catalysts. This work demonstrates that introducing a superhydrophilic catalyst surface structure to dissociate the adsorbed water is a productive strategy to enhance the performance of OER. Furthermore, the rational design of hydrophilic interface materials in this work provides a facile method to developing OER catalysts.
研究领域:
材料科学
·
催化化学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2020
·
IF 5.578
Shaojian Hu,Jianhua Zhu,Bencheng Wu,Rui Ma,Yuechun Chang,Xiaohui Li,Yuqing Wei,Liujie Yu
High viscosity ester base oil, as an eco-friendly lubricant base oil with high performance, can significantly reduce the friction, wear, and energy consumption of large machinery. However, there is less research on the preparation of heterogeneous catalysts for synthesis of high viscosity ester oil. In this work, Sn/Zr mixed oxide catalysts were prepared for the green synthesis of ester base oil with high viscosity. This approach gets rid of additional template, surfactant, organic solvent, sulfur, nitrogen, phosphorus, and halogen, thereby avoiding the potential environmental pollution. A superior powdered catalyst MO-Sn 8 Zr-9.0-160-18 was developed with optimized Sn/Zr molar ratio, pH, hydrothermal temperature, and hydrothermal time of 8:1, 9.0, 160 °C, and 18 h, respectively. Results of catalyst characterization indicated that the developed catalysts were mesoporous materials with hydrophobic properties, allowing for free diffusion of macromolecules, adsorption of reactants, and desorption of water. Additionally, the specific surface area, pore volume, pore diameter, and surface hydrophobicity of catalyst were enhanced by doping Zr, so the catalysts with higher [Sn/Zr] ICP /[Sn/Zr] XPS exhibited better catalytic activity. Preformed catalyst was prepared by simple mechanical mixing method to achieve better catalyst separation. The specific surface area, acid amount, and acid strength of catalyst were indeed improved significantly after catalyst molding. By programmed heating, the preformed catalyst achieved a maximum carboxyl conversion of 97.2%. Moreover, spent catalyst could be reactivated via solvent washing, drying, calcination, and hydrogen reduction, exhibiting good reusability.
研究领域:
化学工程
·
材料科学
·
催化
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2025
·
IF 5.3
Dekang Li,Zhixian Bao,Lijun Jin,Haoquan Hu
Dry reforming of methane (DRM) can spontaneously use CO2 and CH4 to produce syngas, but minimal sulfur impurities in the feed gas can poison and deactivate the catalyst. Although the Ni/Al2O3 catalyst has excellent DRM activity, it is challenging to regenerate due to sulfation of the support. Besides that, the loading of sacrificial promoters used to improve sulfur resistance, such as Cu, may impact the DRM performance of active sites. Here, a spatial separation strategy was proposed to precisely design a sulfur-resistant catalyst, dividing the catalyst into a DRM zone and a H2S adsorption zone. The Ni@SiO2@NiCu catalyst prepared by this strategy shows stable DRM performance and significantly improved sulfur resistance and can be regenerated repeatedly. The Ni@SiO2@NiCu catalyst has the best sulfur resistance, 6.8 times that of the spatially adjacent NiCu@SiO2 catalyst and 1.4 times that of the Ni@SiO2@Cu catalyst. This spatial separation strategy introduces a novel concept for the controllable synthesis of sulfur-resistant catalysts and may inspire further applications in the design and development of such catalysts.
研究领域:
催化化学
·
化学工程
·
材料科学
·
环境科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
KEY ENGINEERING MATERIALS
·
2012
·
IF 0
Zi Li Liu,Cui Xia Xu,Qian Wen Dai,Chao Xiang,Jian Jie Zhang
Supported H3PW12O40 (HPW) and supported Cesium-Substituted dodecatungsto-phosphate are eco-friendly solid acid catalysts. A series of different loading H3PW12O40/SiO2 and HPW/diatomite were prepared by a typical incipient wetness impregnation of methanol, meanwhile SiO2 and diatomite supported Cs-salt catalysts were prepared via two-step impregnating method. The catalysts were investigated by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The results indicate that the Keggin structure of HPW is intact in the SiO2-supported HPW and SiO2-supported CsHPW. HPW and CsHPW are highly dispersed in the SiO2 at the low loading, while the loading is more than 40% the catalyst grains increase and gather on the surface of the carrier. What's more, diatomite is not a suitable support. HPW and CsHPW have better distribution in the SiO2 than in the diatomite. The activity of catalyst was tested in probe experiment of the alkylation of thiopene (TH) with 1-hexene.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Yi Zhao,Yongfeng Lu,Lu Chen,Xiaofeng Wei,Jiefang Zhu,Yuanhui Zheng
Cadmium sulfide (CdS) as one of the most common visible-light-responsive photocatalysts has been widely investigated for hydrogen generation. However, its low solar–hydrogen conversion efficiency caused by fast carrier recombination and poor catalytic activity hinders its practical applications. To address this issue, we develop a novel and highly efficient nickel–cobalt phosphide and phosphate cocatalyst-modified CdS (NiCoP/CdS/NiCoPi) photocatalyst for hydrogen evolution. The dual-cocatalysts were simultaneously deposited on CdS during one phosphating step by using sodium hypophosphate as the phosphorus source. After the loading of the dual-cocatalysts, the photocurrent of CdS significantly increased, while its electrical impedance and photoluminescence emission dramatically decreased, which indicates the enhancement of charge carrier separation. It was proposed that the NiCoP cocatalyst accepts electrons and promotes hydrogen evolution, while the NiCoPi cocatalyst donates electrons and accelerates the oxidation of sacrificial agents (e.g., lactic acid). Consequently, the visible-light-driven hydrogen evolution of this composite photocatalyst greatly improved. The dual-cocatalyst-modified CdS with a loading content of 5 mol % showed a high hydrogen evolution rate of 80.8 mmol·g–1·h–1, which was 202 times higher than that of bare CdS (0.4 mmol·g–1·h–1). This is the highest enhancement factor for metal phosphide-modified CdS photocatalysts. It also exhibited remarkable stability in a continuous photocatalytic test with a total reaction time of 24 h.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）