Applied Catalysis O: Open
·
2024
·
IF 0
Kaiyang Xu,Lingfeng Weng,Lizhi Wu,Li Tan,Yu Tang
Cyclohexanone is a key raw material for manufacturing nylon and other chemicals. The sustainable conversion of biomass-derived phenol to cyclohexanone meets the requirements of sustainable development goal but still be challenging. Herein, a catalyst containing isolated Pd cations in zeolite, namely Pd 1 /ZSM-5, is investigated for the partial hydrogenation of phenol to cyclohexanone. Under 140 °C and 1.5 MPa of initial hydrogen pressure, the conversion of phenol reaches 95.6% with the selectivity to cyclohexanone of 99.9%. Besides, the turnover rate (TOR) of partial hydrogenation of phenol reaches 382.7 h −1 . The mild adsorption affinity of cyclohexanone on catalytic sites leads to the high selectivity. Moreover, as unveiled by surface reactivity of phenol monitored by in-situ infrared spectrum, the oxygen atom of phenol hydroxyl group is adsorbed on the Brönsted acid site of Pd 1 /ZSM-5 as the key reaction step. The reaction intermediate involves the partial hydrogenation of benzene ring of phenol.
研究领域:
催化化学
·
绿色化学
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可持续发展
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生物质转化
✓ 已验证
DOI
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Ziqiang Wang,Zechuan Dai,Hongjie Yu,Hugang Zhang,Wenjing Tian,You Xu,Xiaonian Li,Liang Wang,Hongjing Wang
Electrochemical ammonia synthesis is considered as an alternative sustainable method to the traditional Haber–Bosch process because of the reduced energy consumption and mild operation conditions. The key is to design efficient electrocatalysts for facile adsorption and activation of nitrogen. Herein, a nanoporous Pd film with a tunable pore size has been in situ grown on Ni foam (nPd/NF) via a micelle-assisted replacement method using NF as a reductant and substrate, where polystyrene-b-poly(ethylene oxide) and 1,3,5-triisopropylbenzene serve as a pore-forming agent and a swelling agent, respectively. Combining the continuous large nanoporous structure and self-supported properties, the obtained nPd/NF exhibits excellent catalytic performance for ammonia synthesis with a high NH3 yield of 18.27 μg h–1 mgcat–1 and a faradaic efficiency of 10.36% in 0.1 M Na2SO4. This work provides a fascinating route for the rational design of self-supported porous noble metals with a tunable pore size for effective electrosynthesis of ammonia.
研究领域:
材料科学
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电化学
·
催化化学
✓ 已验证
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2016
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IF 2.653
Huan Wu,Yanmei Zhao,Xuanping Tan,Xiaoqing Zeng,Yuan Guo,Jidong Yang
A convenient fluorescence quenching method for determination of Quizalofop-p-ethyl(Qpe) was proposed in this paper. Eosin Y(EY) is a red dye with strong green fluorescence (λex/λem = 519/540 nm). The interaction between EY, Pd(II) and Qpe was investigated by fluorescence spectroscopy, resonance Rayleigh scattering(RRS) and UV–Vis absorption. Based on changes in spectrum, Pd(II) associated with Qpe giving a positively charged chelate firstly, then reacted with EY through electrostatic and hydrophobic interaction formed ternary chelate could be demonstrated. Under optimum conditions, the fluorescence intensity of EY could be quenched by Qpe in the presence of Pd(II) and the RRS intensity had a remarkable enhancement, which was directly proportional to the Qpe concentration within a certain concentration range, respectively. Based on the fluorescence quenching of EY-Pd(II) system by Qpe, a novel, convenient and specific method for Qpe determination was developed. To our knowledge, this is the first fluorescence method for determination of Qpe was reported. The detection limit for Qpe was 20.3 ng/mL and the quantitative determination range was 0.04–1.0 μg/mL. The method was highly sensitive and had larger detection range compared to other methods. The influence of coexisting substances was investigated with good anti -interference ability. The new analytical method has been applied to determine of Qpe in real samples with satisfactory results.
研究领域:
分析化学
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环境科学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
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IF 5.116
Yimin Zhang,Youhai Cao,Dong Chen,Penglei Cui,Jun Yang
The use of Ionic Liquids (ILs) to enhance the electrocatalytic activity of metal nanoparticles has garnered sustained research interest. However, current strategies involving ionic liquids do not exploit their use and advantages in chemical synthesis of metal nanoparticles. Herein, we demonstrate a straightforward method, which combines the advantages of ILs in nanoparticle synthesis with the potentials of ILs in electrocatalysis , for the synthesis of Pd nanoclusters for electrochemical oxidation of formaldehyde. This method relies on the use of 1-(2′-aminoethyl)-3-methyl-imidazolum tetrafluoroborate ionic liquid as stabilizers to directly generate Pd nanoclusters with average sizes of 1.8 ± 0.3 nm in a reaction medium consisting of water and methanol at room temperature . The electrochemical measurements prove that the ionic liquid-assisted Pd nanoclusters have mass-normalized activity approximately 7 times than that of commercial Pd/C catalysts for the oxidation of formaldehyde.
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
Frontiers in Chemistry
·
2019
·
IF 3.782
Bashir Muhammad Sohail,Jiang Xubao,Li Shusheng,Kong Xiang Zheng
Owing to their high specific surface area and low density, porous polymer materials are of great importance in a vast variety of applications, particularly as supports for enzymes and transition metals. Herein, highly uniform and porous polyurea microspheres (PPM), with size between 200 and 500 μm, are prepared by interfacial polymerization of toluene diisocyanate (TDI) in water through a simple microfluidic device composed of two tube lines, in one of which TDI is flowing and merged to the other with flowing aqueous phase, generating therefore TDI droplets at merging. The polymerization starts in the tube while flowing to the reactor and completed therein. This is a simple, easy and effective process for preparation of uniform PPM. Results demonstrate that the presence of polyvinyl alcohol in the aqueous flow is necessary to obtain uniform PPM. The size of PPM is readily adjustable by changing the polymerization conditions. In addition, palladium is incorporated in PPM to get the composite microspheres Pd@PPM, which are used as catalyst in degradation of methylene blue and rhodamine B. High performance and good reusability are demonstrated. Monodispersity, efficient dye degradation, easy recovery, and remarkable reusability make Pd@PPM a promising catalyst for dye degradation.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 3
·627-634
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IF 5.773
Renfeng Nie,Xiaolun Peng,Haifu Zhang,Xiaolong Yu,Xinhuan Lu,Dan Zhou,Qinghua Xia
Nitrogen-enriched highly mesoporous carbons (NMCs) are synthesized via the one-pot carbonization of biomass-derived glucose and harmless melamine with ZnCl2 as the porogen agent and catalyst. NMC contains an N content of 15.4 wt% and specific surface area of 1017 m2 g−1 with the mesopore volume proportion of 92.1%. Owing to its rich N species and high mesoporosity, NMC can be adapted as a proper support for the fabrication of well-dispersed Pd catalysts for the transfer hydrogenation of vanillin in the water phase with formic acid (FA) as the hydrogen donor. For example, Pd/NMC exhibits 2.9 times higher activity in comparison to nitrogen-free catalysts, and affords 100% vanillin conversion with 2-methoxy-4-methylphenol (MMP) as the sole product. The Pd/NMC catalyst demonstrates enhanced acid-resistance in acid media and adsorption of substrates. It is found that the electron-deficient Pd (Pdδ+) percentage is affected by the N species, and the strong Pd–N interaction generates the co-existence of Pdδ+ and metallic Pd (Pd0), which results in Pd/NMC as a novel bifunctional nanocatalyst for both FA dehydrogenation and vanillin hydrogenation.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Shuaishuai Ding,Chunhua Zhang,Yefei Liu,Hong Jiang,Rizhi Chen
Highly efficient Pd@CN catalysts for selective hydrogenation of phenol to cyclohexanone in water were successfully fabricated by loading Pd nanoparticles (NPs) in N-doped carbons (CN) derived from ZIF-67 with dicyandiamide (DICY) as the additional nitrogen source. For comparison, polyvinylpyrrolidone (PVP) was also used as the additional nitrogen source during the ZIF-67 synthesis. The results showed that the PVP and DICY had significantly different impacts on the microstructures of as-obtained CN materials and the catalytic performance of Pd@CN catalysts in the phenol hydrogenation. The addition of DICY had the positive promotion effect on the surface area of the obtained CN materials. Moreover, the introduction of DICY could increase the nitrogen content of CN and then prevent the re-oxidation of Pd NPs during air contact, resulting in higher Pd 0 ratio. In comparison with PVP, the DICY was more suitable as the additional nitrogen source for the formation of CN and Pd@CN (Pd@CN D , Pd@CN P ). The Pd@CN D exhibited superior catalytic activity as compared to Pd@CN P (phenol conversion 96.9% vs. 67.4%). More importantly, the as-prepared Pd@CN D catalyst could be reused for four times without catalytic performance reduction. The work would aid the development of Pd@CN catalysts with superior catalytic properties.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Jiaying Cui,Nengwu Zhu,Naixin Kang,Chitam Ha,Chaohong Shi,Pingxiao Wu
In this study, the biorecovery mechanism of palladium ions (Pd(II)) as palladium nanoparticles by Enterococcus faecalis ( E. faecalis ), a typical Gram-positive bacterium, was explored from acting force, participated substance and reaction process. The XRD and TEM analysis showed that the deposit locations of Pd-NPs depended on the transfer of Pd(II) in biosorption, and the process was invested by effect factors and theory models of isotherm, thermodynamics, and kinetics, which was a spontaneous endothermic process fitted well by Langmuir isotherm and pseudo-second order kinetics. In addition, the surface characteristic changes of E. faecalis during biorecovery of Pd(II) were compared by FTIR and XPS, and it found that carboxyl groups, hydroxyl groups and amine groups were the main participated functional groups in biorecovery. Furthermore, the contrary pH change between biosorption and bioreduction combined with above results proved that electrostatic interaction, complex formation of Pd(II) on the cell and intracellular uptake were the acting forces for biosorption, and the bioreduction of adsorbed Pd(II) was via the hydrolysis and oxidation of sodium formate to deliver electron. Therefore, the biorecovery mechanism of Pd(II) can be divided into the biosorption from solution to cells, and then the bioreduction and crystallization in situ by the electron donor and the link frame of E. faecalis .
研究领域:
微生物学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2018
·
IF 3.974
Yuan Chen,Yuancai Chen,Jingyi Wu,Jianyi Zhang
In this paper, we found a bacteria ( Bacillus wiedmannii MSM) that could not only culture quickly under aerobic condition , but also can biological reduction of Pd (II) under both aerobic and anaerobic conditions. For reducing Pd (II) by Bacillus wiedmannii MSM, the best electron donor was sodium formate and the best growth time was 24 h (mid-log growth phase cells). TEM indicated that a lot of palladium nanoparticles (Pd-NPs) were mainly located in the periplasmic space of the live cells. However, the autoclaved cells could not synthesize Pd-NPs, which proved the role of enzyme in the reduction of Pd (II). A few of Pd-NPs were only formed on the surface of Cu 2+ -treated cells, which proved the main but not the only role of periplasmic hydrogenase in the reduction of Pd (II). XRD and XPS also proved that Pd-NPs could be synthesized by live cells over broad ranges of temperature (20–40 °C) and pH (pH 3.0–7.0). This may be especially useful for in situ reduction and remediation of Pd (II) for both anaerobic and aerobic wastewater.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 114
·94008-94015
·
IF 3.84
Fen Guo,Ke Ye,Xiaomei Huang,Yinyi Gao,Kui Cheng,Guiling Wang,Dianxue Cao
A novel Pd/polyaniline/CFC electrode is prepared by electroless deposition of palladium (Pd) onto three-dimensional polyaniline networks. The polyaniline matrix on the carbon fiber cloth (CFC) in the reduction state is electro-synthesized by cyclic voltammetry and has a lower vertex potential of −0.4 V vs. Ag/AgCl. The particle size of the Pd coated on the polyaniline chains is gradiently distributed. The as-prepared Pd/polyaniline/CFC electrode is characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FITR) and X-ray diffraction (XRD). The hydrogen peroxide (H2O2) electro-reduction reaction in H2SO4 solutions on the Pd/polyaniline/CFC electrode is investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The results reveal that the electrode exhibited high catalytic activity and excellent stability in the strong oxidizing solution of H2O2 and H2SO4. Polyaniline itself shows electro-catalytic activity towards H2O2 to some extent involving the chemical–electrochemical (C–E) coupling mechanism.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2017
·
IF 3.473
Tiantian Chen,Tingwen Wei,Zhijie Zhang,Yahui Chen,Jian Qiang,Fang Wang,Xiaoqiang Chen
Highly sensitive and selective fluorescent probes 1 and 2 for detection of palladium ions (Pd 2+ ) were synthesized based on excited-state intramolecular proton transfer process (ESIPT) using 2-(2′-hydroxy-)benzothiazole moiety. Different metal ions were used to optimize their sensitivity and selectivity but best results were obtained with Pd 2+ . Probe 1 produced green fluorescence with Stokes shift of about 163 nm upon addition of Pd 2+ , whereas probe 2 displayed red fluorescence with a large Stokes shift of about 217 nm under similar conditions. The detection limits of 1 and 2 to Pd 2+ were found to be 285 nM and 14.6 nM, respectively. Mechanistic aspects of probes 1 and 2 were discussed to account for the optical changes leading to the strong ESIPT fluorescence in very short duration. Furthermore, the portable test strips were also prepared by direct deposition of the probe molecules onto the filter paper to detect the lowest possible ppm levels of Pd 2+ .
研究领域:
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Lu Lin,Haiou Liu,Xiongfu Zhang
Rational design of efficient approaches to fabricate MOFs-coated core-shell composites is promising but challenging. We report here the encapsulation of Pd nanoparticles (Pd NPs) supported flower-like ZnO (F-ZnO) microspheres with ZIF-8 shell through a facile strategy, in which the formation and immobilization of Pd NPs on F-ZnO supports and the subsequent growth of ZIF-8 shells over them are effectively integrated into one-pot synthetic route. Importantly, the utilization of ZnO both as support of Pd NPs and Zn 2+ source of ZIF-8 is favorable for the implement of one-pot synthesis, due to its functions in anchoring Pd NPs and inducing ZIF-8 formation. Further insights into the morphological influence of zinc oxide particles on the resulting materials indicate that the flower-like microspheres with 2D nanosheets as subunits also benefit the coating of Pd NPs supported cores with ZIF-8, resulting in a well-defined core-shell catalyst. The achieved catalyst deliveries remarkable performance in terms of selectivity, anti-poisoning and recyclability in the liquid hydrogenations of alkenes.
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
危险品化学品经营许可证（带存储）