A Pt-Bi bimetallic nanoparticle catalyst for direct electro-oxidation of formic acid in fuel cells
Shu-Hong LI, Yue ZHAO, Jian CHU, Wen-Wei LI, Han-Qing YU, Gang LIU, Yang-Chao TIAN
《环境科学与工程前沿(英文)》
2013年
第7卷
第3期
页码 388-394
doi:
10.1007/s11783-012-0475-y
摘要:
Direct formic acid fuel cells are a promising portable power-generating device, and the development of efficient anodic catalysts is essential for such a fuel cell. In this work Pt-Bi nanoparticles supported on micro-fabricated gold wire array substrate were synthesized using an electrochemical deposition method for formic acid oxidation in fuel cells. The surface morphology and element components of the Pt-Bi/Au nanoparticles were characterized, and the catalytic activities of the three Pt-Bi/Au nanoparticle electrodes with different Pt/Bi ratios for formic acid oxidation were evaluated. It was found that Pt Bi /Au had a much higher catalytic activity than Pt Bi /Au and Pt Bi /Au, and Pt Bi /Au exhibited a current density of 2.7 mA·cm , which was 27-times greater than that of Pt/Au. The electro-catalytic activity of the Pt-Bi/Au electrode for formic acid oxidation increased with the increasing Bi content, suggesting that it would be possible to achieve an efficient formic acid oxidation on the low Pt-loading. Therefore, the Pt-Bi/Au electrode offers a promising catalyst with a high activity for direct oxidation of formic acid in fuel cells.
关键词:
catalyst
electrochemical deposition
formic acid oxidation
fuel cell
gold wire array
microfabrication
Dechlorination of dichlorodiphenyltrichloroethane (DDT) by Fe/Pd bimetallic nanoparticles: Comparison
Kubra Ulucan-Altuntas, Eyup Debik
《环境科学与工程前沿(英文)》
2020年
第14卷
第1期
doi:
10.1007/s11783-019-1196-2
摘要:
DDT undergoes dechlorination via Fe/Pd bimetallic nanoparticle. The oxidation effect of nZVI on DDT is greatly improved when Pd is dopped. The highest concentration to be treated under cancerogenesis limit was 110 mg/L. The dechlorination of DDT is more like to DDE via Fe/Pd but to DDD via nZVI. Degradation products concentrations are lowered via Fe/Pd when compared with nZVI. In this study, the bimetallic Fe/Pd nanoparticle was synthesized using the catalytic element palladium to increase the effect of nano zero valent iron (nZVI), in the light of the information obtained from our previous study, in which the nZVI synthesis method was modified. Dichlorodiphenyltrichloroethane (DDT), one of the most widely used persistent organic pollutant pesticides in the world, was investigated in terms of its degradation by Fe/Pd nanoparticles and the difference with nZVI was determined. During the study, the Fe/Pd concentration, initial DDT concentration, and contact time were selected as variables affecting the treatment. The highest possible initial DDT concentration for the treatment with Fe/Pd bimetallic nanoparticle was investigated to obtain the DDT effluent concentration below the carcinogenesis limit, 0.23 µg/L. The highest concentration that could be treated was found to be 109.95 mg/L with Fe/Pd. It was found that 44.3 min of contact time and 550 mg/L Fe/Pd concentration were needed to achieve this treatment.
关键词:
Persistent organic pollutants
nZVI
Bimetallic nanoparticle
Organochlorine pesticides
DDT
Ni-Co bimetallic catalyst for CH
Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI
《化学科学与工程前沿(英文)》
2010年
第4卷
第4期
页码 476-480
doi:
10.1007/s11705-010-0512-y
摘要:
A co-precipitation method was employed to prepare Ni/Al O -ZrO , Co/Al O -ZrO and Ni-Co/Al O -ZrO catalysts. Their properties were characterized by N adsorption (BET), thermogravimetric analysis TGA , temperature-programmed reduction (TPR), temperature-programmed desorption (CO -TPD), and temperature-programmed surface reaction (CH -TPSR and CO -TPSR). Ni-Co/Al O -ZrO bimetallic catalyst has good performance in the reduction of active components Ni, Co and CO adsorption. Compared with mono-metallic catalyst, bimetallic catalyst could provide more active sites and CO adsorption sites (C+ CO = 2CO) for the methane-reforming reaction, and a more appropriate force formed between active components and composite support (SMSI) for the catalytic reaction. According to the CH -CO -TPSR, there were 80.9% and 81.5% higher CH and CO conversion over Ni-Co/Al O -ZrO catalyst, and its better resistance to carbon deposition, less than 0.5% of coke after 4 h reaction, was found by TGA. The high activity and excellent anti-coking of the Ni-Co/Al O -ZrO catalyst were closely related to the synergy between Ni and Co active metal, the strong metal-support interaction and the use of composite support.
关键词:
Ni-Co bimetallic catalyst
composite support
CH4 reforming with CO2
Enhanced activation of persulfate using mesoporous silica spheres augmented Cu–Al bimetallic oxide particles
《化学科学与工程前沿(英文)》
2023年
第17卷
第10期
页码 1581-1592
doi:
10.1007/s11705-023-2327-7
摘要:
Herein, Cu–Al bimetallic oxide was synthesized and mixed with mesoporous silica spheres via a simple hydrothermal method. The prepared sample was then analyzed and employed to activate potassium peroxydisulfate for bisphenol A removal. Based on the results of X-ray diffraction, scanning electron microscopy, and energy dispersion spectroscopy, Cu–Al bimetallic oxide was determined as CuO-Al2O3, and mesoporous silica spheres were found around the these particles. At 30 min, a bisphenol A degradation level of 90% was achieved, and it remained at over 60% after five consecutive cycles, indicating the catalyst’s superior capacity and stability. In terms of removal performance, the radical pathway (including , OH •, and ) and singlet oxygen () played minor roles, while electron migration between bisphenol A, potassium peroxydisulfate, and the catalyst played a dominant role. The introduction of Al2O3 promoted the formation of surface oxygen vacancies, which improved ligand complex formation between potassium peroxydisulfate and the catalyst, thereby facilitating electron migration. Furthermore, mesoporous silica spheres augment not only enhanced bisphenol A adsorption but also alleviated Cu leaching. Overall, this work is expected to provide significant support for the rational development of catalysts with high catalytic activity for persulfate activation via surface electron migration.
关键词:
Cu–Al bimetallic oxides
mesoporous silica spheres
peroxydisulfate
bisphenol A
Removing polybrominated diphenyl ethers in pure water using Fe/Pd bimetallic nanoparticles
Min ZHANG,Jian LU,Zhencheng XU,Yiliang HE,Bo ZHANG,Song JIN,Brian BOMAN
《环境科学与工程前沿(英文)》
2015年
第9卷
第5期
页码 832-839
doi:
10.1007/s11783-015-0778-x
摘要:
Polybrominated diphenyl ethers (PBDEs) have been widely used as fire-retardants. Due to their high production volume, widespread usage, and environmental persistence, PBDEs have become ubiquitous contaminants in various environments.Nanoscale zero-valent iron (ZVI) is an effective reductant for many halogenated organic compounds. To enhance the degradation efficiency, ZVI/Palladium bimetallic nanoparticles (nZVI/Pd) were synthesized in this study to degrade decabromodiphenyl ether (BDE209) in water. Approximately 90% of BDE209 was rapidly removed by nZVI/Pd within 80 min, whereas about 25% of BDE209 was removed by nZVI. Degradation of BDE209 by nZVI/Pd fits pseudo-first-order kinetics. An increase in pH led to sharply decrease the rate of BDE209 degradation. The degradation rate constant in the treatment with initial pH at 9.0 was more than 6.8 × higher than that under pH 5.0. The degradation intermediates of BDE209 by nZVI/Pd were identified and the degradation pathways were hypothesized. Results from this study suggest that nZVI/Pd may be an effective tool for treating polybrominated diphenyl ethers (PBDEs) in water.
关键词:
degradation
bimetallic nanoparticles
nanoscale zero-valent iron
polybrominated diphenyl ethers
Enhanced activity of bimetallic Fe-Cu catalysts supported on ceria toward water gas shift reaction: synergistic
《化学科学与工程前沿(英文)》
2023年
第17卷
第12期
页码 1962-1972
doi:
10.1007/s11705-023-2359-z
摘要:
Within the “hydrogen chain”, the high-temperature water gas shift reaction represents a key step to improve the H2 yield and adjust the H2/COx ratio to fit the constraints of downstream processes. Despite the commercial application of the high-temperature water gas shift, novel catalysts characterized by higher intrinsic activity (especially at low temperatures), good thermal stability, and no chromium content are needed. In this work, we propose bimetallic iron-copper catalysts supported on ceria, characterized by low active phase content (iron oxide + copper oxide < 5 wt %). Fresh and used samples were characterized by inductively coupled plasma mass spectrometry, X-ray diffraction, nitrogen physisorption, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, and temperature programmed reduction in hydrogen to relate physicochemical features and catalytic activity. The sample with iron/copper ≈ 1 and 4 wt % active phase content showed the best catalytic properties in terms of turnover frequency, no methane formation, and stability. Its unique properties were due to both strong iron-copper interaction and strong metal-support interaction, leading to outstanding redox behavior.
关键词:
water gas shift
iron
copper
bimetallic catalysts
ceria
hydrogen
Mechanistic understanding of Cu-based bimetallic catalysts
You Han, Yulian Wang, Tengzhou Ma, Wei Li, Jinli Zhang, Minhua Zhang
《化学科学与工程前沿(英文)》
2020年
第14卷
第5期
页码 689-748
doi:
10.1007/s11705-019-1902-4
摘要:
Copper has received extensive attention in the field of catalysis due to its rich natural reserves, low cost, and superior catalytic performance. Herein, we reviewed two modification mechanisms of co-catalyst on the coordination environment change of Cu-based catalysts: (1) change the electronic orbitals and geometric structure of Cu without any catalytic functions; (2) act as an additional active site with a certain catalytic function, as well as their catalytic mechanism in major reactions, including the hydrogenation to alcohols, dehydrogenation of alcohols, water gas shift reaction, reduction of nitrogenous compounds, electrocatalysis and others. The influencing mechanisms of different types of auxiliary metals on the structure-activity relationship of Cu-based catalysts in these reactions were especially summarized and discussed. The mechanistic understanding can provide significant guidance for the design and controllable synthesis of novel Cu-based catalysts used in many industrial reactions.
关键词:
copper
bimetallic catalyst
coordination
modification mechanism
catalytic application
Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study
《化学科学与工程前沿(英文)》
2023年
第17卷
第12期
页码 1986-2000
doi:
10.1007/s11705-023-2337-5
摘要:
Breakage of the C–N bond is a structure sensitive process, and the catalyst size significantly affects its activity. On the active metal nanoparticle scale, the role of catalyst size in C–N bond cleavage has not been clearly elucidated. So, Ru catalysts with variable nanoparticle sizes were obtained by modulating the reduction temperature, and the catalytic activity was evaluated using 1,2,3,4-tetrahydroquinoline and o-propylaniline with different C–N bond hybridization patterns as reactants. Results showed a 13 times higher reaction rate for sp3-hybridized C–N bond cleavage than sp2-hybridized C–N bond cleavage, while the reaction rate tended to increase first and then decrease as the catalyst nanoparticle size increased. Different concentrations of terrace, step, and corner sites were found in different sizes of Ru nanoparticles. The relationship between catalytic site variation and C–N bond cleavage activity was further investigated by calculating the turnover frequency values for each site. This analysis indicates that the variation of different sites on the catalyst is the intrinsic factor of the size dependence of C–N bond cleavage activity, and the step atoms are the active sites for the C–N bond cleavage. When Ru nanoparticles are smaller than 1.9 nm, they have a strong adsorption effect on the reactants, which will affect the catalytic performance of the Ru catalyst. Furthermore, these findings were also confirmed on other metallic Pd/Pt catalysts. The role of step sites in C–N bond cleavage was proposed using the density function theory calculations. The reactants have stronger adsorption energies on the step atoms, and step atoms have d-band center nearer to the Fermi level. In this case, the interaction with the reactant is stronger, which is beneficial for activating the C–N bond of the reactant.
关键词:
sp3/sp2-hybridized C–N bond
noble metal nanoparticle
catalytic active site
turnover frequency
DFT
Iron oxide nanoparticle-based theranostics for cancer imaging and therapy
Xiaoqing REN,Hongwei CHEN,Victor YANG,Duxin SUN
《化学科学与工程前沿(英文)》
2014年
第8卷
第3期
页码 253-264
doi:
10.1007/s11705-014-1425-y
摘要:
Theranostic platform, which is equipped with both diagnostic and therapeutic functions, is a promising approach in cancer treatment. From various nanotheranostics studied, iron oxide nanoparticles have advantages since IONPs have good biocompatibility and spatial imaging capability. This review is focused on the IONP-based nanotheranostics for cancer imaging and treatment. The most recent progress for applications of IONP nanotheranostics is summarized, which includes IONP-based diagnosis, magnetic resonance imaging (MRI), multimodal imaging, chemotherapy, hyperthermal therapy, photodynamic therapy, and gene delivery. Future perspectives and challenges are also outlined for the potential development of IONP based theranostics in clinical use.
关键词:
theranostics
iron oxide nanoparticles
MRI
drug delivery
photothermal therapy
photodynamic therapy
Nanoparticle-enhanced coolants in machining: mechanism, application, and prospects
《机械工程前沿(英文)》
2023年
第18卷
第4期
doi:
10.1007/s11465-023-0769-8
摘要:
Nanoparticle-enhanced coolants (NPECs) are increasingly used in minimum quantity lubrication (MQL) machining as a green lubricant to replace conventional cutting fluids to meet the urgent need for carbon emissions and achieve sustainable manufacturing. However, the thermophysical properties of NPEC during processing remain unclear, making it difficult to provide precise guidance and selection principles for industrial applications. Therefore, this paper reviews the action mechanism, processing properties, and future development directions of NPEC. First, the laws of influence of nano-enhanced phases and base fluids on the processing performance are revealed, and the dispersion stabilization mechanism of NPEC in the preparation process is elaborated. Then, the unique molecular structure and physical properties of NPECs are combined to elucidate their unique mechanisms of heat transfer, penetration, and anti-friction effects. Furthermore, the effect of NPECs is investigated on the basis of their excellent lubricating and cooling properties by comprehensively and quantitatively evaluating the material removal characteristics during machining in turning, milling, and grinding applications. Results showed that turning of Ti‒6Al‒4V with multi-walled carbon nanotube NPECs with a volume fraction of 0.2% resulted in a 34% reduction in tool wear, an average decrease in cutting force of 28%, and a 7% decrease in surface roughness Ra, compared with the conventional flood process. Finally, research gaps and future directions for further applications of NPECs in the industry are presented.
关键词:
nanoparticle-enhanced coolant
minimum quantity lubrication
biolubricant
thermophysical properties
turning
milling
grinding
标题
作者
时间
类型
操作
A Pt-Bi bimetallic nanoparticle catalyst for direct electro-oxidation of formic acid in fuel cells
Shu-Hong LI, Yue ZHAO, Jian CHU, Wen-Wei LI, Han-Qing YU, Gang LIU, Yang-Chao TIAN
期刊论文
Dechlorination of dichlorodiphenyltrichloroethane (DDT) by Fe/Pd bimetallic nanoparticles: Comparison
Kubra Ulucan-Altuntas, Eyup Debik
期刊论文
Ni-Co bimetallic catalyst for CH
Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI
期刊论文
Enhanced activation of persulfate using mesoporous silica spheres augmented Cu–Al bimetallic oxide particles
期刊论文
Fabrication of bimetallic Cu–Zn adsorbents with high dispersion by using confined space for gas adsorptive
期刊论文
Removing polybrominated diphenyl ethers in pure water using Fe/Pd bimetallic nanoparticles
Min ZHANG,Jian LU,Zhencheng XU,Yiliang HE,Bo ZHANG,Song JIN,Brian BOMAN
期刊论文
Enhanced activity of bimetallic Fe-Cu catalysts supported on ceria toward water gas shift reaction: synergistic
期刊论文
Mechanistic understanding of Cu-based bimetallic catalysts
You Han, Yulian Wang, Tengzhou Ma, Wei Li, Jinli Zhang, Minhua Zhang
期刊论文
Performance of iron-air battery with iron nanoparticle-encapsulated C–N composite electrode
期刊论文
Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study
期刊论文
Iron oxide nanoparticle-based theranostics for cancer imaging and therapy
Xiaoqing REN,Hongwei CHEN,Victor YANG,Duxin SUN
期刊论文
Nanoparticle-enhanced coolants in machining: mechanism, application, and prospects
期刊论文
Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen
期刊论文
Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient
期刊论文
The synergic effects of highly selective bimetallic Pt-Pd/SAPO-41 catalysts for the
Guozhi Jia, Chunmu Guo, Wei Wang, Xuefeng Bai, Xiaomeng Wei, Xiaofang Su, Tong Li, Linfei Xiao, Wei Wu
期刊论文