CHINESE JOURNAL OF CATALYSIS
·
2013
·Vol. 34
·期 12
·2161-2166
·
IF 1.304
Mingming Zhang,Manman Jiang,Changhai Liang
A basic anion exchange resin , Amberlite IRA-900, was loaded with Pd(C 3 H 5 )(C 5 H 5 ) by an easy metal-organic chemical vapor deposition (MOCVD) approach to give Pd@IRA-900 catalyst after reduction at room temperature . Ultraviolet-Visible spectroscopy results showed a red shift of the absorption peak of Pd 2+ after the Pd precursor was loaded on the resin, indicating that a chemical reaction occurred between the precursor and the support. Pd nanoparticles with 2.6 nm of average size were well dispersed on the support. The Pd@IRA-900 catalyst showed high activity for different kinds of aryl halides in Suzuki-Miyaura coupling reactions under mild and aerobic conditions. Excellent recyclability of Pd@IRA-900 catalyst was also observed in the Suzuki-Miyaura coupling reaction of iodobenzene and phenylboronic acid . A bifunctional catalyst Pd@IRA-900(OH) was synthesized by pretreating the ion exchange resin support with NaOH before Pd loading, which successfully catalyzed the Suzuki-Miyaura reaction of iodobenzene and phenylboronic acid without base under aerobic conditions.
研究领域:
催化化学
·
有机合成
·
材料化学
·
绿色化学
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纳米催化
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 72
·45420-45431
·
IF 3.108
Jiuli Guo,Huanhuan Yu,Feng Dong,Baolin Zhu,Weiping Huang,Shoumin Zhang
A highly efficient and stable Au–Cu/hydroxyapatite (HAP, Ca10(PO4)6(OH)2) catalyst was reported. HAP was prepared through a deposition–precipitation method. Au–Cu/HAP catalysts were obtained by a two-step impregnation approach. The samples were characterized by XRD, TEM, SEM, UV-Vis, ICP, XPS, H2-TPR, and O2-TPD. CO oxidation reaction was carried out to evaluate the catalytic performance of samples. TEM and UV-Vis results showed that the metallic particles supported on Au–Cu/HAP were smaller than those on Au/HAP, and they were highly dispersed on the HAP support. Patterns of XPS revealed that CuO nanoparticles were formed in the Cu/HAP catalyst, while CuO and Cu2O species coexisted in Au–Cu/HAP catalyst. Based on the O2-TPD data, the addition of copper to Au/HAP gave rise to more new O2 adsorption sites and bigger O2 adsorption capacity. The catalysis results indicated that the Au–Cu/HAP was capable of obtaining higher efficiency and stability compared with Au/HAP and Cu/HAP for CO oxidation. It was likely that the synergistic interaction between gold and CuOx phase created the most active sites on Au–Cu/HAP and was responsible for the enhanced activity and stability in comparison with Au/HAP and Cu/HAP.
研究领域:
催化化学
·
材料科学
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环境化学
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纳米催化
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表面科学
✓ 已验证
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2015
·Vol. 94
·期 3
·424-429
·
IF 1.231
Xia Gui,Ying Ding,Zhi Yun
An integrated approach was developed for preparing epoxy fatty acid methyl esters (EFAMEs) from cottonseed using a two-phase solvent extraction (TPSE) process followed by sequential base-catalyzed transesterification and epoxidation reactions. The TPSE process was performed to achieve simultaneous production of high-quality crude cottonseed oil and nontoxic cottonseed meal. The base-catalyzed transesterification of the cottonseed oil proceeded smoothly at 30 °C over 2 h to provide a high yield of fatty acid methyl esters (FAMEs). Subsequent epoxidation of the unsaturated FAMEs using petroleum ether as a non-polar solvent, H 3 PO 4 as a catalyst, 0.3 g/g H 2 O 2 as an oxygen donor, and HCOOH as an oxygen carrier gave the corresponding EFAMEs with a conversion to oxirane of 0.85 g/g. The order of effectiveness of catalysts was found to be H 3 PO 4 > TiO 2 > H 2 SO 4 > strong-acid cation exchange resin. The bio-based integrated process and new methods for the preparation of modified EFAMEs show great promise for comprehensive development and commercial applications of cottonseed with fewer steps and lower cost.
研究领域:
应用化学
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油脂化学
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生物基材料
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绿色化工
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天然产物转化
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 118
·97256-97263
·
IF 3.84
Qianqian Huang,Weiqiang Yu,Rui Lu,Fang Lu,Jin Gao,Hong Miao,Jie Xu
Catalytic conversion and application of bio-based platform chemicals is of great significance. Itaconic acid, one of the abundant and renewable bio-based platform chemicals, could be hydrogenated to produce methylsuccinic acid, which has important applications in pharmaceutical synthesis. Traditional catalysts can be corroded, leached and deactivated in an acid reaction environment, and the stability of the catalysts is a great challenge. Carbothermal reduction was employed to prepare stable ruthenium-based catalysts, and the results confirmed that CO generated in situ functioned as an efficient reducing species in the carbothermal reduction process. The catalysts were applied for the hydrogenation of itaconic acid, and showed good stability and resistance to acid with no obvious loss of activity and less leaching in recycling tests compared to hydrogen reduced samples which exhibited an apparent decrease of 22% for the conversion of itaconic acid. The carbothermal reduced catalysts could maintain 99% conversion and 99% selectivity for methylsuccinic acid, and maintained good stability and acid-resistance under a higher temperature and longer reaction time.
研究领域:
催化化学
·
绿色化学
·
生物质转化
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有机合成
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材料化学
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工业催化
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可持续能源
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2016
·
IF 2.437
Bin Xu,Tao Ding,Yongcai Zhang,Yaoting Wen,Zhanjun Yang,Ming Zhang
This communication reports the development of a new efficient visible-light-driven composite photocatalyst comprising ZnFe 2 O 4 nanoparticles and conjugated polymer (CPVC) from the dehydrochlorination of polyvinyl chloride (PVC). ZnFe 2 O 4 /CPVC nanocomposites were synthesized via three main steps: (i) the synthesis of ZnFe 2 O 4 nanoparticles by a sol-gel method; (ii) the adsorption of PVC in tetrahydrofuran solution by ZnFe 2 O 4 nanoparticles to form ZnFe 2 O 4 /PVC nanocomposites; and (iii) the dehydrochlorination of PVC in the ZnFe 2 O 4 /PVC nanocomposites by heating at 150 °C for 2 h. X-ray diffraction, Fourier transform infrared spectroscopy and high-resolution transmission electron microscopy characterization revealed that the as-synthesized product was core/shell structured ZnFe 2 O 4 /CPVC nanocomposites. The photocatalytic results demonstrated that the ZnFe 2 O 4 /CPVC nanocomposites had much higher photocatalytic activity than ZnFe 2 O 4 nanoparticles in the reduction of aqueous Cr(VI) under visible-light (λ>420 nm) irradiation. Thus, ZnFe 2 O 4 /CPVC nanocomposites are promising for use as a new efficient visible-light-driven photocatalyst .
研究领域:
材料科学
·
环境化学
·
纳米技术
·
光催化
·
高分子化学
✓ 已验证
DOI
高影响因子
Small
·
2020
·Vol. 16
·期 22
·2000870
·
IF 11.459
Kezhong Lv,Pengfei Wang,Chao Wang,Zihan Shen,Zhenda Lu,Huigang Zhang,Mingbo Zheng,Ping He,Haoshen Zhou
Lithium–sulfur batteries, as one of promising next-generation energy storage devices, hold great potential to meet the demands of electric vehicles and grids due to their high specific energy. However, the sluggish kinetics and the inevitable “shuttle effect” severely limit the practical application of this technology. Recently, design of composite cathode with effective catalysts has been reported as an essential way to overcome these issues. In this work, oxygen-deficient ferric oxide (Fe 2 O 3− x ), prepared by lithiothermic reduction, is used as a low-cost and effective cathodic catalyst. By introducing a small amount of Fe 2 O 3− x into the cathode, the battery can deliver a high capacity of 512 mAh g −1 over 500 cycles at 4 C, with a capacity fade rate of 0.049% per cycle. In addition, a self-supporting porous S@KB/Fe 2 O 3− x cathode with a high sulfur loading of 12.73 mg cm −2 is prepared by freeze-drying, which can achieve a high areal capacity of 12.24 mAh cm −2 at 0.05 C. Both the calculative and experimental results demonstrate that the Fe 2 O 3− x has a strong adsorption toward soluble polysulfides and can accelerate their subsequent conversion to insoluble products. As a result, this work provides a low-cost and effective catalyst candidate for the practical application of lithium–sulfur batteries.
研究领域:
电化学
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能源材料
·
纳米催化
·
储能技术
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Jing Jiang,Jiayi Zhang,Baihao Wu,Sheng Tu
The regulation of the metal-support interaction in heterogeneous catalysts can promote the activation of reactants, which is beneficial for the hydrolytic dehydrogenation reaction. Herein, the hydrolytic dehydrogenation of dimethylamine borane (DMAB) is systematically studied on the oxygen vacancy (O v ) enriched Pt-Co 3 O 4 heterogeneous catalyst with the metal-support interaction. It is found that the metallic Pt site facilitates the adsorption of DMAB molecules and the O v on Co 3 O 4 support as an electron-rich center cooperates with the adjacent Pt site to dissociate water molecules. The in situ Raman and attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy reveal the effective activation and cleavage of the O-H in water and the B-H in DMAB over the Pt-Co 3 O 4 catalyst. The optimal Pt-Co 3 O 4 catalyst exhibits the extraordinary activity for the catalytic hydrolysis of DMAB at 303 K, delivering a high specific hydrogen generation rate (64063 mL min −1 g pt −1 ) and a competitive turnover frequency (TOF, 23880 mol H2 mol Pt −1 h −1 ). This performance outperforms most of the reported heterogeneous catalysts for DMAB dehydrogenation . More importantly, the Pt-Co 3 O 4 catalyst achieves the desirable on-demand hydrogen production by using special chemical switches. This finding provides the fundamental understanding of metal-oxide systems with the collaborative interfacial catalysis for boosting DMAB dehydrogenation .
研究领域:
催化化学
·
纳米材料科学
·
能源化学
·
表面科学
·
多相催化
·
氢能存储与释放
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 1
·
IF 1.866
Zhaowei Wang,Zhixia Wen,Xing Li,Junwei Yu,Xiaoxuan Liu
The preparation of the high cis −1,4-polyisoprene by Ziegler-Natta catalysis system was studied. The effect of Al-Ti catalysts modified by ethers with different structures which are different electron donor reagent on polymerization of isoprene has been mainly investigated. By the measurement method of the monomer conversion, FTIR, and 1 H NMR spectroscopy, the influence of, respectively, added diphenyl ether, anisole, dibutyl ether, or methyl tert -butyl methyl ether as a third active component on the heterogeneous TiCl 4 -Al( i -Bu) 3 -ether catalyst activity and microstructure of synthetic polyisoprene was analyzed. By the adding of diphenyl ether or dibutyl ether, the process of prefabricated heterogeneous catalyst is quickly and catalyst particle quantity is large. The polymerization conversion is high and the microstructure cis −1,4 content of the resulting polymer can reach 92%. But Al( i -Bu) 3 added anisole or methyl tert -butyl methyl ether hard to cooperate with TiCl 4 . © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 44357.
研究领域:
高分子化学
·
催化化学
·
功能材料
·
合成高分子
·
配位聚合
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2019
·
IF 7.723
Yuanyuan Ma,Zhongling Lang,Jing Du,Likai Yan,Yonghui Wang,Huaqiao Tan,Shifa Ullah Khan,Yang Liu,Zhenhui Kang,Yangguang Li
Selective reduction of nitroarenes is extremely valuable in industrial chemical production. The main reduced products are usually aniline derivatives obtained using single-component noble- or transition-metal catalysts; however, other important products such as hydrazobenzene derivatives always involve in harsh conditions and multiple reaction steps. Here, we realize an unexpected switchable reduction of nitroarenes into aniline or hydrazobenzene derivatives with high yield and selectivity just by controlling the molar ratio of nitroarenes to N 2 H 4 ·H 2 O with a nickel–tungsten carbide composite nanocatalyst loaded on carbon (Ni-WC/C). A series of control experiments and density functional theory (DFT) calculations indicate that the multiple interfaces between Ni and WC can induce a synergistic effect, significantly modulating the electronic structure of the Ni-WC/C catalyst, and endowing the catalyst with switchable selectivity and high activity for the reduction of nitroarenes by hydrogenation. This synergistic multi-interfacial catalyst may offer a new way to design and explore highly efficient and selective catalysts for the controllable reduction of nitroarenes and similar hydrogenation reactions.
研究领域:
催化化学
·
有机合成
·
纳米材料
·
表面科学
·
工业化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Xiaolong Liu,Qingzhen Han,Wenbo Shi,Cheng Zhang,Erwei Li,Tingyu Zhu
In this work, ruthenium-based bimetallic catalysts of 1Ru-5 M/TiO 2 (M = Co, Ce, Fe, Mn, Cu, Ni) were prepared and evaluated in ethyl acetate oxidation. It was found that 1Ru-5Cu/TiO 2 gave the highest catalytic activity. The influence of CuO content and the preparation method on the catalytic activity was also studied. 1Ru-5Cu/TiO 2 showed great catalytic stability in the on-stream reaction test. The influence of H 2 O on the catalytic activity is presented. The bimetallic catalyst 1Ru-5Cu/TiO 2 showed better catalytic performance than the monometallic catalysts 1Ru/TiO 2 and 5Cu/TiO 2 . XRD, TEM, HAADF-STEM, H 2 -TPR, and XPS characterizations were conducted, and the synergistic effect between Ru and Cu was well presented. In situ FTIR studies were also conducted, and the reaction intermediates were revealed on the catalyst surface. The theoretical calculations suggested that ethyl acetate is more easily adsorbed on the CuO surface, while it reacts more easily on the RuO 2 surface . Accordingly, a reaction mechanism for the catalytic oxidation of ethyl acetate over a Ru-Cu bimetallic catalyst is proposed.
研究领域:
催化化学
·
环境化学
·
表面科学
·
材料化学
·
物理化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Xiong Wang,Zhenyou Li,Xiaoyu Han,Zhengang Han,Yongxiao Bai
Porous organic Polymers (POPs) can not only exhibit high specific surface area and pore volume, but also tunable pore size distribution. Herein, copolymers of 2-hydroxyethylmethylacrylate (HEMA) and divinylbenzene (DVB) with specific pore structure were synthesized via a dispersion polymerization strategy, and then immobilized metallocene catalysts with well-defined pore structure were obtained on the produced POP supports. The nitrogen sorption and Gel permeation chromatography (GPC) results demonstrate that the pore structure of the immobilized metallocene catalyst is highly dependent on the pore structure of the POPs , and the pore structure of metallocene catalysts or the POPs has a significant influence on the molecular chain growth of the produced polyethylene. By tuning the distribution of the active species scattered in the micro- and the narrow meso-pore range (roughly ≤4 nm), the chain growth of the polyolefin can be tailored effectively during the polymerization process, although differential scanning calorimetry (DSC) and temperature rising elution fractionation (TREF) results show that the chemical composition distributions (CCDs) of produced PE from the POPs-supported metallocene catalysts are not determined by polymerization activity or molecule chain length, but mainly by the active site species scattered in the supported catalysts. Scanning electron micrograph (SEM) shows that the produced polyethylene has highly porous fabric which consists of nanofiber and spherical beads of micron dimension.
研究领域:
高分子化学
·
催化化学
·
材料科学
·
纳米材料
·
聚合物科学
·
石油化工
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·Vol. 9
·期 4
·105292
·
IF 5.909
Jie Zhou,Wenyi Cai,Jing Ding,Hui Wan,Guofeng Guan
The appropriate construct of Z-scheme heterostructure composite with high photocatalytic activity has created new opportunities for environmental protection. Herein, graphitic carbon nitride quantum dots/tungsten trioxide (CNQDs/WO 3 ) was firstly fabricated using CNQDs decorated onto the surface of WO 3 nanorod grown along the [110] orientation in hydrothermal environment to construct a Z-scheme heterostructure composite. By various characterization methods, the crystal structure, micro morphology, atomic valence state and surface functional groups of the catalyst were systematically revealed. The results indicated that Z-scheme heterojunctions between CNQDs and WO 3 were successfully constructed. Compared with pure WO 3 , CNQDs/WO 3 exhibited prominent photoreduction performance under visible light irradiation. The optimal 5% CNQDs/WO 3 could reduce almost 100% Cr (VI) under acidic condition with the best photocatalytic activity within 90 min. More than this, 5% CNQDs/WO 3 also displayed excellent stability and recyclability even after five cycles of photoreduction experiments. Based on the free radical quenching experiments, the possible photoreduction reaction mechanism had been proposed in detail. The Z-scheme heterostructure provided the possibility of the generation, rapidly transfer and efficient separation of photogenerated electrons, which were major active species in the Cr (VI) photoreduction process.
研究领域:
环境催化
·
材料化学
·
纳米科技
·
光催化
·
环境污染治理
·
半导体异质结
✓ 已验证
DOI
高影响因子