ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2019
·
IF 4.527
Jinghao Wang,Sijing Bi,Yuancai Chen,Yongyou Hu
Gram-negative Citrobacter freundii with high Pd (II) reduction capacity was isolated from electroplating wastewater, and the electron transfer involved in Pd (II) bio-reduction by C. freundii JH was investigated in phosphate buffer saline solution with sodium formate as sole electron donor under anaerobic condition . FTIR spectra indicated that hydroxyl and amine groups on cell wall participated Pd (II) bio-sorption. TEM , XRD, XPS results confirmed that Pd (0) nanoparticles (NPs) could be bio-synthesized intra/extracellularly. Meanwhile, pH turn-over were observed owing to the reduction of cytochrome c (c-Cyt) in bio-reduction process. EPR spectra indicated that free radicals ( OH) was generated from high concentration Pd (II), which would cause seriously damage to cell. Despite of the lower tolerance to Pd (II), the cells at logarithmic phase exhibited higher Pd (II) reduction capacity (72.21%) than that at stationary phase (56.21%), which might be related to the relatively stronger proton motive force (PMF) created by the substrate oxidation and the electron transfer, as evidenced by electrochemical experiments (CV, DPV, amperometric I-t curves) and protein denaturalization experiments. Additionally, c-Cyt and riboflavin were confirmed to be important participants in electron transfer. Finally, a putative synthesis mechanism of Pd (0)-NPs was deduced. This study contributed to further understanding the electron transfer in Pd (II) reduction, and provided more information for the bio-synthetic of metal nanoparticles.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2019
·Vol. 12
·期 3
·2126-2132
·
IF 6.97
Hui Xu,Hongyuan Shang,Cheng Wang,Liujun Jin,Chunyan Chen,Yukou Du
Although great successes have been accomplished on the controlled synthesis of 2D and 3D Pd-containing nanomaterials, tapping into the novel Pd-containing electrocatalysts that combined the advantages of both 2D and 3D structures remains a significant challenge. Here, an approach to systematically produce porous Fe-doped Pd nanosheet assemblies (NSAs) with a geometry tuning from PdFe hollow nanospheres (HNSs), PdFe nanocages (NCs), to PdFe nanoplates (NPs) is reported. The inherent ultrathin and porous features endow these PdFe catalysts with excellent electrocatalytic performance. As a result, the optimized 3D PdFe NCs show a much-improved methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR) activities in comparison with PdFe HNSs, Pd NPs, and commercial Pd/C catalysts. Moreover, these PdFe nanocatalysts also display greatly enhanced electrocatalytic stability, which can endure 500 cycles with negligible activity loss and structural changes. The mechanism investigations reveal that the introduced Fe atom efficiently modulates the electronic structure of Pd, leading to the downshift of the d-band center of Pd, which is beneficial for the adsorption of reactants. Moreover, the porous nanosheet assembly structure can provide rich mass and electron transfer channels, further boosting the improvement of electrocatalytic performance.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Jian Lu,Yingying Qin,Chao Yu,Xinyu Lin,Minjia Meng,Yongsheng Yan,Hougang Fan,Yilin Wu,Chunxiang Li
Pd (II) from release-unbridled electroplating wastewater is causing great challenges, which is unfavourable either to human health or resource reutilization. Ion-imprinted membranes (IIMs) have recently drawn attentions for selective separation of specific ions from analogues. In this context, we have developed a facile strategy for fabrication of Pd (II)-imprinted membranes (Pd-IIMs) for the selective separation of Pd (II). The enhanced flux was obtained by three-dimensional macroporous structure on polydimethylsiloxane (PDMS). Then the Pd-IIMs were synthesized by a modification-imprinting strategy based on PDMS substrates. With the existence of Co (II), Cu (II), Cd (II) and Ni (II), the as-obtained Pd-IIMs showed superior adsorptive selectivity (3.32–5.06) and perm-selectivity (2.34–4.04) towards Pd (II), as well as the satisfactory regeneration performance (more than 92% of the initial rebinding capacities after 5 cycles of adsorption/desorption). Moreover, the as-prepared Pd-IIMs also displayed stability on separation factors even under ultrasonic treatment. Notably, the overused Pd-IIMs after applications for selective separation of Pd (II) showed a satisfactory performance for the treatment of methylene blue (99.87%), which displayed potentials for the “further applications”. The Pd-IIMs and preparation strategy developed in this work have shown a positive opportunity for the efficient treatment of electroplating wastewater and organic dyes.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2019
·
IF 2.752
Xiao Jiang,Qing-Da An,Zuo-Yi Xia,Shang-Ru Zhai,L. Zhong-Cheng,Kai Wang
In this study, N-doped platelet-like metal-loaded Zr/SBA-15 was synthesized and employed for reducing 4-nitrophenol to remove this contaminant from water. Dopamine hydrochloride was used as a novel CN source for the modification of ZrSBA-15. The N doping process occurred readily at a low temperature due to the polymerization of dopamine, which could save energy and simplify the experimental fabrication of catalysts. In addition, polydopamine can immobilize Pd ions in a facile manner and the trapped Pd ions are reduced to Pd nanoparticles due to the reducibility of the polydopamine polymer. The utilization of dopamine allows the catalyst to be obtained in a facile and cost-effective synthetic process, while the production of the CN layer as well as the reduction and immobilization of the Pd ions can occur simultaneously. Characterization of the product showed that the catalyst had a platelet-like structure after decoration with elemental Zr, which enhanced the catalytic reaction compared with the natural fiber-like SBA-15. The optimal Pd loading capacity was determined as ~3.0 wt% and the materials obtained could reduce 4-nitrophenol to 4-aminophenol within 120 s with a conversion ratio above 90%.
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2019
·Vol. 16
·期 4
·1904964
·
IF 10.856
Zelin Chen,Yunwei Liu,Chang Liu,Jinfeng Zhang,Yanan Chen,Wenbin Hu,Yida Deng
The development of new type electrocatalysts with promising activity and antipoisoning ability is of great importance for electrocatalysis on alcohol oxidation. In this work, Pd nanowire (PdNW)/CuO x heterogeneous catalysts with different types of Pd O Cu interfaces (Pd/amorphous or crystalline CuO x ) are prepared via a two-step hydrothermal strategy followed by an air plasma treatment. Their interface-dependent performance on methanol and ethanol oxidation reaction (MOR and EOR) is clearly observed. The as-prepared PdNW/crystalline CuO x catalyst with 17.2 at% of Cu on the PdNW surface exhibits better MOR and EOR activity and stability, compared with that of PdNW/amorphous CuO x and pristine PdNW catalysts. Significantly, both the cycling tests and the chronoamperometric measurements reveal that the PdNW/crystalline CuO x catalyst yields excellent tolerance toward the possible intermediates including formaldehyde, formic acid, potassium carbonate, and carbon monoxide generated during the MOR process. The detailed analysis of their chemical state reveals that the enhanced activity and antipoison ability of the PdNW/crystalline CuO x catalyst originates from the electron-deficient Pd δ+ active sites which gradually turn into Pd 5 O 4 species during the MOR catalysis. The Pd 5 O 4 species can likely be stabilized by moderate crystalline CuO x decorated on the surface of PdNW due to the strong Pd O Cu interaction.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2019
·
IF 0
Ting Qu,Qiang Tan,Yingjie Chen,Liting Liu,Shengwu Guo,Yuanzhen Chen,Yan Liu,Sai Li,Yongning Liu
Direct alcohol fuel cell technology (DAFC) has gained significant interest recently as it is a green energy technology with a low/zero pollution emission. Nevertheless, the sluggish kinetics of the electrocatalysis process and the high cost of anode catalysts still impede the wide application of DAFC. Moreover, the limited understanding of the reaction mechanism restrains the development of anode catalysts. Here, we have prepared a Pd-(SnO2@C)/C catalyst and highlighted a strategy to demonstrate the effects of active oxygen-contained species and electronic interaction, which are identified to have a synergistic effect. The as-prepared Pd-(SnO2@C)/C catalyst showed remarkable activity and stability for EOR and MOR in alkaline media. It also had an encouraging performance in a polymer fiber membrane-based alkaline DAFC, where a NiCo2O4 catalyst was used for the oxygen cathode. Combined with the theoretical analysis and the experimental research results, this study reveals that the electronic interaction is the dominant mechanism in the synergistic effect, which provides theoretical guidance and technical support for the preparation of the next generation of high catalytic activity and high stability anode catalysts of DAFC.
✓ 已验证
产品关联
DOI
Catalysts
·
2019
·Vol. 9
·期 10
·834
·
IF 3.444
Jun Zhou,Xiaoqing Cao,Hongna Wang,Song Li
The catalytic oxidation of silanes to produce silanols using water as an oxidant at mild temperatures is a major challenge in Si-H activation. Highly efficient and easy-to-recycle catalysts based on Pd nanoparticles are in high demand. In this study, Pd nanoparticles embedded in an MgO porous overlayer on an Mg plate as a structured catalyst was prepared by the plasma electrolyte oxidation (PEO) technique. The Pd/MgO catalyst is strongly anchored to the MgO plate, building a structured catalyst. Fabrication parameters such as the temperature of the electrolyte and applied voltage significantly influenced the structure of the obtained Pd/MgO catalyst and in turn its catalytic activity. The catalytic activities of Pd/MgO were evaluated by activation of a Si-H bond for catalyzing the aqueous oxidation of silanes to silanol at mild temperatures. The catalytic activity of Pd nanoparticles is favored by their electro-deficient state due to influence from the MgO substrate. The Pd/MgO catalyst exhibits good performance stability during recycling. This work paves the way for fabricating structured catalysts with long-term stability and enhanced metal–oxide interaction.Keywords:structured catalyst;Pd nanoparticles;metal–oxide interaction;silanol
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2022
·
IF 6.449
Zexiao Zhang,Jiahui Wei,Bing Yuan,Fengli Yu,Congxia Xie,Shitao Yu
An aqueous phase Pd nanoparticles (NPs) system reduced and stabilized only by sodium lignosulfonate (SLS) was found to exhibit a favorable catalytic performance in hydrodeoxygenation of vanillin to produce 2-methoxy-4-methylphenol (MMP). Ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) characterization were carried out to confirm the formation of NPs, and the influence of various metal salt precursors, temperatures, stirring rates and SLS concentrations on catalyst preparation. It was revealed that the optimized Pd NPs with an average diameter of 14.63 nm had achieved a 99.8 % vanillin conversion and a 98.6 % MMP selectivity under the conditions of 1 mmol vanillin, n (Vanillin) / n (Pd) = 300, 1 MPa H 2 , 70 °C and 2 h. Besides, MMP, the target product, was found an auto-separation property from the aqueous catalyst system due to its less solubility in water. Furthermore, this aqueous Pd NPs catalyst was demonstrated to have stable catalytic activity in the hydrodeoxygenation of vanillin by ten-run tests with favorable conversions of vanillin above 98 %. The selectivity of MMP stayed above 92 % within five runs and still maintained 85.4 % after ten runs. Thus, an environmentally friendly and mild-conditioned hydrodeoxygenation method of vanillin into MMP was developed by using SLS, one of the by-products of the pulp and paper industry.
✓ 已验证
产品关联
DOI
高影响因子
Chemistry-An Asian Journal
·
2022
·Vol. 17
·期 24
·e202200993
·
IF 4.839
Zhijie Zhu,Xu Hu,Xingda An,Mengqi Xiao,Liang Zhang,Chaoran Li,Le He
Graphical The influence of the composition of bimetallic nanocrystals on their performance of photothermal catalytic CO 2 hydrogenation was investigated. Pd and Ni play different roles in the photothermal catalytic processes in the bimetallic system, which leads to a functional tradeoff over the stoichiometric ratio. Bimetallic nanomaterials exhibit excellent catalytic performance in photothermal CO 2 hydrogenation due to the synergistic effect between the two metal components. However, the component-performance relationship remains unclear, which hinders the design of efficient bimetallic catalysts and the investigation of catalytic reaction mechanism. Here we illustrate the influence of the composition of binary alloy on their performance of photothermal catalytic CO 2 hydrogenation by using monodispersed Pd−Ni nanocrystal as an example. Our study reveals that Ni and Pd play a significantly different role in the catalytic processes. Higher Ni component in the catalysts could lead to stronger light absorption, higher activity, and lower CO selectivity. The optimized Pd 4 Ni 1 −SiO 2 catalyst exhibited a near-unity and stable CO production rate of 230 mmol ⋅ g −1 ⋅ h −1 under 25-sun illumination. This study paves the way for the usage of bimetal in photothermal CO 2 catalysis towards more efficient solar-to-chemical energy conversions, and sheds light on some general design principles of bimetallic catalysts to balance the intrinsic properties of individual components.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Mengxiao Zhong,Maoqiang Chi,Yun Zhu,Ce Wang,Xiaofeng Lu
Controllable fabrication of novel and uniform noble metal nanoparticles on a specific support with a superior catalytic or electrocatalytic performance is of significantly importance for practical applications. In this report, we demonstrated an effective way to fabricate uniform thin-walled Pd/polypyrrole (PPy) hollow nanotubes . The prepared Pd/PPy hybrid nanotubes exhibited an excellent peroxidase-like activity to oxidize a typical peroxidase substrate such as 3,3′,5,5′-tetramethylbenzidine in comparison with traditional Pd/C and Pd black catalysts. The outstanding catalytic activity of the Pd/PPy hybrid nanotubes for peroxidase mimicking could be resulting from their unique hollow characteristic and an interfacial effect between PPy and Pd components. Based on the favorable catalytic property of the Pd/PPy hybrid nanotubes, a convenient and rapid colorimetric way to sensitively determine ascorbic acid has been presented. The detection limit was around 0.062 μM and an excellent selectivity was also achieved. The developed detection system in this study could be extended to the fields of bioscience and biotechnology with promising prospects.
研究领域:
生物化学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2017
·
IF 4.217
Yunhua Li,Xing Zhang,Hua Zhang,Binghui Chen,Kevin J. Smith
This work compares the stability of Ni 2 P/SiO 2 , Pd/SiO 2 and Pd-Ni 2 P/SiO 2 catalysts during phenol hydrodeoxygenation (HDO) in the presence of H 2 O. The Pd-Ni 2 P/SiO 2 catalyst (PNP) was prepared by an in-situ reduction method in which PdCl 2 is added directly to unpassivated Ni 2 P/SiO 2 . A series of physicochemical characterizations, such as X-Ray diffraction, transmission electron microscopy, thermogravimetry, temperature programmed reduction and X-ray photoelectron spectroscopy were used. The results showed that the PNP catalyst has the highest stability among these catalyts. Phenol conversion and cyclohexane selectivity vary from 100.0% to 93.0% and from 94.2% to 83.1%, respectively with 0.1 g catalyst at 2 MPa and 493 K in four reaction cycles. Enhanced stabiltiy is attributed to Pd highly dispersed and strongly interacting with Ni 2 P on the PNP catalyst, resulting in negligible aggregation and loss of metal as well as very low carbon formation over the PNP catalyst. In contrast, the deactivation of Pd/SiO 2 results from aggregation and loss of Pd, while that of Ni 2 P/SiO 2 is due to the loss of phosphorus, phosphide oxidation and carbon deposition in the presence of H 2 O.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2023
·Vol. 16
·期 1
·335-342
·
IF 6.7
Yinglei Liu,Chicheng Ma,Jiye Zhang,Huiying Zhou,Gaowu Qin,Song Li
The electronic interaction between a metal and a support modulates the electronic structures of supported metals and plays an important role in manipulating their catalytic performance. However, this interaction is mainly realized in heterogeneous catalysts composed of reducible oxides. Herein, we demonstrate the electronic interaction between γ-Al2O3 and η-Al2O3 with varying acid–base properties and supported Pd nanoparticles (NPs) of 2 nm in size. The strength and number of acid–base sites on the supports and catalysts were systemically characterized by FT-IR spectroscopy and TPD. The supported Pd NPs exhibit electron-rich surface properties by receiving electrons from the electron-donating basic sites on γ-Al2O3, which are beneficial for catalyzing the hydrogenation of nitrobenzene. In contrast, Pd NPs loaded on η-Al2O3 are electron-deficient because of the rich electron-withdrawing acid sites of η-Al2O3. As a result, Pd/η-Al2O3 exhibits higher catalytic activity in phenylacetylene hydrogenation than Pd/γ-Al2O3. Our results suggest a promising route for designing high-performance catalysts by adjusting the acid–base properties of Al2O3 supports to maneuver the electronic structures of metals.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）