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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    

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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    

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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    

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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 SO4•‒, OH •, and O2•‒) and singlet oxygen (1O2) 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    

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Fabrication of bimetallic Cu–Zn adsorbents with high dispersion by using confined space for gas adsorptive

《化学科学与工程前沿（英文）》   页码 1623-1631 doi: 10.1007/s11705-022-2202-y

摘要： The number of active components and their dispersion degree are two key factors affecting the performance of adsorbents. Here, we report a simple but efficient strategy for dispersing active components by using a confined space, which is formed by mesoporous silica walls and templates in the as-prepared SBA-15 (AS). Such a confined space does not exist in the conventional support, calcined SBA-15, which does not contain a template. The Cu and Zn precursors were introduced to the confined space in the AS and were converted to CuO and ZnO during calcination, during which the template was also removed. The results show that up to 5 mmol·g–1 of CuO and ZnO can be well dispersed; however, severe aggregation of both oxides takes place in the sample derived from the calcined SBA-15 with the same loading. Confined space in the AS and the strong interactions caused by the abundant hydroxyl groups are responsible for the dispersion of CuO and ZnO. The bimetallic materials were employed for the adsorptive separation of propene and propane. The samples prepared from the as-prepared SBA-15 showed superior performance to their counterparts from the calcined SBA-15 in terms of both adsorption capacity of propene and selectivity for propene/propane.

关键词： bimetallic adsorbents     confined space     mesoporous silica     propene/propane separation    

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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    

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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    

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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    

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Performance of iron-air battery with iron nanoparticle-encapsulated C–N composite electrode

《能源前沿（英文）》 doi: 10.1007/s11708-023-0913-5

摘要： Highly efficient and stable iron electrodes are of great significant to the development of iron-air battery (IAB). In this paper, iron nanoparticle-encapsulated C–N composite (NanoFe@CN) was synthesized by pyrolysis using polyaniline as the C–N source. Electrochemical performance of the NanoFe@CN in different electrolytes (alkaline, neutral, and quasi-neutral) was investigated via cyclic voltammetry (CV). The IAB was assembled with NanoFe@CN as the anode and IrO2 + Pt/C as the cathode. The effects of different discharging/charging current densities and electrolytes on the battery performance were also studied. Neutral K2SO4 electrolyte can effectively suppress the passivation of iron electrode, and the battery showed a good cycling stability during 180 charging/discharging cycles. Compared to the pure nano-iron (NanoFe) battery, the NanoFe@CN battery has a more stable cycling stability either in KOH or NH4Cl + KCl electrolyte.

关键词： energy storage and conversion     metallic composites     nanocomposites     iron-air battery     iron anode    

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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    

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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    

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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    

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Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1550-1560 doi: 10.1007/s11705-021-2104-4

摘要： The low cost and highly efficient construction of electrocatalysts has attracted significant attention owing to the use of clean and sustainable energy technologies. In this work, cobalt nanoparticle decorated N-doped carbons (Co@NC) are synthesized by the pyrolysis of a cobalt covalent organic framework under an inert atmosphere. The Co@NC demonstrates improved electrocatalytic capabilities compared to N-doped carbon without the addition of Co nanoparticles, indicating the important role of cobalt. The well-dispersed active sites (Co-Nx) and the synergistic effect between the carbon matrix and Co nanoparticles greatly enhance the electrocatalytic activity for the oxygen reduction reaction. In addition, the Co content has a significant effect on the catalytic activity. The resulting Co@NC-0.86 exhibits a superb electrocatalytic activity for the oxygen reduction reaction in an alkaline electrolyte in terms of the onset potential (0.90 V), half-wave potential (0.80 V) and the limiting current density (4.84 mA·cm–2), and a high selectivity, as well as a strong methanol tolerance and superior durability, these results are comparable to those of the Pt/C catalyst. Furthermore, the superior bifunctional activity of Co@NC-0.86 was also confirmed in a home-built Zn-air battery, signifying the possibility for application in electrode materials and in current energy conversion and storage devices.

关键词： cobalt embedment     N-doped carbons     covalent organic framework     oxygen reduction     Zn-air battery    

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Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient

《化学科学与工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11705-023-2378-9

摘要： In this study, we synthesize a catalyst comprising cobalt nanoparticles supported on MXene by pyrolyzing a composite in a N2 environment. Specifically, the composite comprises a bimetallic Zn/Co zeolitic imidazole framework grown in situ on the outer surface of MXene. The catalytic efficiency of the catalyst is tested for the self-coupling of 4-methoxybenzylamine to produce value-added imine, where atmospheric oxygen (1 atm) is used as the oxidant. Based on the results, the catalyst displayed impressive catalytic activity, achieving 95.4% yield of the desired imine at 383 K for 8 h. Furthermore, the catalyst showed recyclability and tolerance toward benzylamine substrates with various functional groups. The outstanding performance of the catalyst is primarily attributed to the synergetic catalytic effect between the cobalt nanoparticles and MXene support, while also benefiting from the three-dimensional porous structure. Additionally, a preliminary investigation of potential reaction mechanisms is conducted.

关键词： MXene     sacrificial template     oxidative self-coupling     Co nanoparticles     imine    

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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

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1111-1124 doi: 10.1007/s11705-020-2031-9

摘要： The hydroisomerization of -hexadecane over Pt-Pd bimetallic catalysts is an effective way to produce clean fuel oil. This work reports a useful preparation method of bimetallic bifunctional catalysts by a co-impregnation or sequential impregnation process. Furthermore, monometallic catalysts with loading either Pt or Pd are also prepared for comparison. The effects of the metal species and impregnation order on the characteristics and catalytic performance of the catalysts are investigated. The catalytic test results indicate that the maximum -hexadecane yield over different catalysts increases as follows: Pt/silicoaluminophosphate SAPO-41

关键词： SAPO-41 molecular sieve     Pt-Pd bimetallic site     bifunctional catalysts     n-hexadecane     hydroisomerization    

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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