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A facile synthesis of high activity cube-like Pt/carbon composites for fuel cell application

Reza B. MOGHADDAM, Samaneh SHAHGALDI, Xianguo LI

《能源前沿（英文）》 2017年 第11卷 第3期   页码 245-253 doi: 10.1007/s11708-017-0492-4

摘要： High activity catalyst with simple low-cost synthesis is essential for fuel cell commercialization. In this study, a facile procedure for the synthesis of cube-like Pt nanoparticle (Pt ) composites with high surface area carbon supports is developed by mixing precursor of Pt with carbon supports in organic batches, hence, one pot synthesis. The Pt grow with Vulcan XC-72 or Ketjen black, respectively, and then treated for 5.5 h at 185ºC (i.e., Pt /V and Pt /K). The resulting particle sizes and shapes are similar; however, Pt /K has a larger electrochemical active surface area (EASA) and a remarkably better formic acid (FA) oxidation performance. Optimization of the Pt /K composites leads to Pt /K that has been treated for 10 h at 185ºC. With a larger EASA, Pt /K is also more active in FA oxidation than the other Pt /K composites. Impedance spectroscopy analysis of the temperature treated and as-prepared (i.e., untreated) Pt /K composites indicates that Pt /K is less resistive, and has the highest limiting capacitance among the Pt /K electrodes. Consistently, the voltammetric EASA is the largest for Pt /K. Furthermore, Pt /K is compared with two commercial Pt/C catalysts, Tanaka Kikinzoku Kogyo (TKK), and Johnson Matthey (JM)Pt/C catalysts. The TKK Pt/C has a higher EASA than Pt /K, as expected from their relative particles sizes (3–4 nm vs. 6–7 nm for Pt /K), however, Pt /K has a significantly better FA oxidation activity.

关键词： synthesis     cube-like Pt     Pt/C composite     catalyst     impedance    

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Pt–C interactions in carbon-supported Pt-based electrocatalysts

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1677-1697 doi: 10.1007/s11705-023-2300-5

摘要： Carbon-supported Pt-based materials are highly promising electrocatalysts. The carbon support plays an important role in the Pt-based catalysts by remarkably influencing the growth, particle size, morphology, dispersion, electronic structure, physiochemical property and function of Pt. This review summarizes recent progress made in the development of carbon-supported Pt-based catalysts, with special emphasis being given to how activity and stability enhancements are related to Pt–C interactions in various carbon supports, including porous carbon, heteroatom doped carbon, carbon-based binary support, and their corresponding electrocatalytic applications. Finally, the current challenges and future prospects in the development of carbon-supported Pt-based catalysts are discussed.

关键词： Pt–C interactions     Pt-based materials     carbon support     electrocatalysis    

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Ionic liquid modified Pt/C electrocatalysts for cathode application in proton exchange membrane fuel

Huixin Zhang, Jinying Liang, Bangwang Xia, Yang Li, Shangfeng Du

《化学科学与工程前沿（英文）》 2019年 第13卷 第4期   页码 695-701 doi: 10.1007/s11705-019-1838-8

摘要： The modification of Pt/C catalyst by using ionic liquids to improve their catalyst activities has been reported by many researchers, but their practical behavior in operating fuel cells is still unknown. In this work, we study the ionic liquid modified Pt/C nanoparticle catalysts within cathodes for proton exchange membrane fuel cells. The influence of the ionic liquid amount, adsorption times and dispersing solvents are investigated. The experiment results show the best performance enhancement is achieved through two-time surface modification with 2 wt-% ionic liquid solution. The mechanisms are explored with the attribution to the high oxygen solubility in the ionic liquid enabling an improved oxygen diffusion in micropores and to good hydrophobicity facilitating water expelling from the active sites in fuel cell operation.

关键词： ionic liquid     PEMFC     electrode     oxygen reduction reaction     electrocatalyst     adsorption    

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Pt/C催化剂电子结构调控产氢介观动力学研究 Article

陈文尧, 傅文钊, 段学志, 陈炳旭, 钱刚, 司锐, 周兴贵, 袁渭康, 陈德

《工程（英文）》 2022年 第14卷 第7期   页码 124-133 doi: 10.1016/j.eng.2020.11.014

摘要：

通过调控金属-载体界面间的电子传递提高催化性能已被证明是一种有效且具有挑战性的催化研究策略。本文提出了一种调变铂/碳纳米复合物催化剂中碳载体表面化学性质（载体表面吸电子/给电子含氧官能团），用以精细调控负载金属铂电子性质及其催化性能的方法。本文以氨硼烷水解制氢作为模型反应，结合密度泛函理论（DFT）计算、先进表征技术、动力学及同位素研究，定量关联了载体表面化学性质、铂电荷数与电子结合能、活化熵与活化焓，以及催化活性之间的关系。通过解耦碳载体表面复杂的影响因素，提出铂电荷数可作为实验易测量的催化活性描述符，其中通过铂电荷数的调变可使催化性能提升15倍。在此基础上，首次建立了包含催化剂活性描述符与活性位数量的介观动力学模型，可分别定量催化剂电子与几何效应，并预测催化性能的变化。本文提出的介观动力学模型可进一步用于设计与构筑高效的金属/碳催化剂。

关键词： 介观动力学模型     催化剂描述符     铂电荷数     碳表面化学     产氢活性    

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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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Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 146-150 doi: 10.1007/s11705-007-0027-3

摘要： The performance of the polymer electrolyte membrane fuel cell (PEMFC) is greatly controlled by the structure of the catalyst layer. Low catalyst utilization is still a significant obstacle to the commercialization of the PEMFC. In order to get a fundamental understanding of the electrode structure and to find the limiting factor in the low catalyst utilization, it is necessary to develop the mechanical model on the effect of catalyst layer structure on the catalyst utilization and the performance of the PEMFC. In this work, the structure of the catalyst layer is studied based on the lattice model with the Monte Carlo simulation. The model can predict the effects of some catalyst layer components, such as Pt/C catalyst, electrolyte and gas pores, on the utilization of the catalyst and the cell performance. The simulation result shows that the aggregation of conduction grains can greatly affect the degree of catalyst utilization. The better the dispersion of the conduction grains, the larger the total effective area of the catalyst is. To achieve higher utilization, catalyst layer components must be distributed by means of engineered design, which can prevent aggregation.

关键词： catalyst utilization     PEMFC     commercialization     Pt/C catalyst     conduction    

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Valveless pumping using a two-stage impedance pump

C.-C. LEE, Y. A. ABAKR, K.-C. WOO

《机械工程前沿（英文）》 2013年 第8卷 第3期   页码 311-318 doi: 10.1007/s11465-013-0270-x

摘要：

Impedance pump is defined as a type of valveless pumping mechanism, where an elastic tube is joined with a tube of different impedance, a periodic asymmetrical compression on part of the elastic tube will produce a unidirectional flow. Numerical and experimental studies had been conducted in the past, but little experimental work was found to exploit the principle of multi-stage impedance pumping for fluid transportation. This paper concentrates on the fluid behavior for an open-loop two-stage system experimentally. The aim of this work is to have an insight on the deliverable head and pumping rate of an open-loop two-stage impedance pumping system. This paper generally investigates the effect of different parameters towards the generation of unidirectional flows and composite flow of two opposite directions. Results obtained are of significant values.

关键词： valveless pumping     open-loop     two-stage     unidirectional     composite    

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The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

《化学科学与工程前沿（英文）》 2022年 第16卷 第3期   页码 397-407 doi: 10.1007/s11705-021-2076-4

摘要： The catalytic hydrogenation of carboxylic acid to alcohols is one of the important strategies for the conversion of biomass. Herein, a series of Ni-doped PtSn catalysts were prepared, characterized and studied in the hydrogenation of acetic acid. The Ni dopant has a strong interaction with Pt, which promotes the hydrogen adsorption, providing an activated hydrogen-rich environment for the hydrogenation. Meanwhile, the presence of Ni also improves the Pt dispersion, giving more accessible active sites for hydrogen activation. The cooperation of Pt and Ni significantly promotes the catalytic activity of the hydrogenation of acetic acid to ethanol. As a result, the catalyst with 0.1% Ni exhibits the best reaction activity, and its space time yield is twice as that of the PtSn/SiO2 catalyst. It provides a meaningful instruction on the catalyst design for the carboxylic acid hydrogenation.

关键词： acetic acid     ethanol     hydrogenation     Pt     Ni     cooperation effect    

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Decoration of CdMoO micron polyhedron with Pt nanoparticle and their enhanced photocatalytic performance

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 1949-1961 doi: 10.1007/s11705-023-2360-6

摘要： This study aimed to prepare and apply a novel Pt/CdMoO4 composite photocatalyst for photocatalytic N2 fixation and tetracycline degradation. The Pt/CdMoO4 composite was subjected to comprehensive investigation on the morphology, structure, optical properties, and photoelectric chemical properties. The results demonstrate the dispersion of Pt nanoparticles on the CdMoO4 surface. Close contact between CdMoO4 and Pt was observed, resulting in the formation of a heterojunction structure at their contact region. Density functional theory calculation and Mott-Schottky analysis revealed that Pt possesses a higher work function value than CdMoO4, resulting in electron drift from CdMoO4 to Pt and the formation of a Schottky barrier. The presence of this barrier increases the separation efficiency of electron-hole pairs, thereby improving the performance of the Pt/CdMoO4 composite in photocatalysis. When exposed to simulated sunlight, the optimal Pt/CdMoO4 catalyst displayed a photocatalytic nitrogen fixation rate of 443.7 μmol·L‒1·g‒1·h‒1, which is 3.2 times higher than that of pure CdMoO4. In addition, the composite also exhibited excellent performance in tetracycline degradation, with hole and superoxide species identified as the primary reactive species. These findings offer practical insights into designing and synthesizing efficient photocatalysts for photocatalytic nitrogen fixation and antibiotics removal.

关键词： photocatalytic N2 fixation     Pt/CdMoO4     tetracycline degradation     Schottky barrier    

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NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

《化学科学与工程前沿（英文）》 2023年 第17卷 第4期   页码 373-386 doi: 10.1007/s11705-022-2223-6

摘要： The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability. Considering the close connection between their performance and the amount of carbon material loaded on the electrodes, in this work, NiCo2O4 nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction. Then, the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo2O4 nanowires, and the obtained composite was used as electrode for electric double layer capacitor. The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF∙cm–2 at the current density of 1 mA∙cm–2. The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW∙h∙cm–3 at a power density of 180 mW∙cm–3. The assembled symmetric capacitor exhibited a capacitance retention of 88.96% after 10000 charge/discharge cycles at the current density of 20 mA∙cm–2. These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.

关键词： carbon cloth     NiCo2O4 nanowires     core−shell structure     quinone-rich     electric double layer capacitor    

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Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 369-377 doi: 10.1007/s11705-014-1435-9

摘要： Catalysts Pt/TiO and NiMo/Al O are highly active and selective for the hydrodeoxygenation of guaiacol in a fixed bed reactor at 300 °C and 7.1 MPa, leading to the hydrogenation of aromatic ring, followed by demethylation and dehydroxylation to produce cyclohexane. For a complete hydrodeoxygenation of guaiacol, metal sites and acid sites are required. NiMo/Al O and Pt/Al O are more active and selective for cyclohexane formation as compared with Pt/TiO at 285 °C and 4 MPa. However, Pt/TiO is stable while the other two catalysts deactivate due to the nature and amount of coke formation during the reaction.

关键词： Pt/TiO2     NiMo/Al2O3     Pt/Al2O3     bio-oil     hydrodeoxygenation     guaiacol     cyclohexane    

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potassium ion-responsive copolymer into polysulfone support membrane on the performance of thin-film composite

Meibo He, Zhuang Liu, Tong Li, Chen Chen, Baicang Liu, John C. Crittenden

《化学科学与工程前沿（英文）》 2019年 第13卷 第2期   页码 400-414 doi: 10.1007/s11705-018-1757-0

摘要： Thin-film composite (TFC) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (PIP) and 1,3,5-benzenetricarbonyl trichloride on polysulfone (PSf) support membranes blended with K -responsive poly( -isopropylacryamide-co-acryloylamidobenzo-15-crown-5) (P(NIPAM-co-AAB C )). Membranes were characterized by attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscope, contact angle, and filtration tests. The results showed that: (1) Under K -free conditions, the blended P(NIPAM-co-AAB C )/PSf supports had porous and hydrophilic surfaces, thereby producing NF membranes with smooth surfaces and low MgSO rejections; (2) With K in the PIP solution, the surface roughness and water permeability of the resultant NF membrane were increased due to the K -induced transition of low-content P(NIPAM-co-AAB C ) from hydrophilic to hydrophobic; (3) After a curing treatment at 95 °C, the improved NF membrane achieved an even higher pure water permeability of 10.97 L·m ·h ·bar under 200 psi. Overall, this study provides a novel method to improve the performance of NF membranes and helps understand the influence of supports on TFC membranes.

关键词： nanofiltration     interfacial polymerization     support membrane     potassium ion-responsive     thin-film composite    

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高性能多功能水泥基复合材料 Article

Victor C. Li

《工程（英文）》 2019年 第5卷 第2期   页码 250-260 doi: 10.1016/j.eng.2018.11.031

摘要：

混凝土是一种不断发展的材料，甚至高性能混凝土的定义也正随着时间的推移而发生变化。本文所说的混凝土材料的高性能特性是指那些直接影响我们生活质量的民用基础设施的理想耐久性、回弹性和可持续性的特性。这些特性包括拉伸延展性、自体裂缝宽度控制和材料的“绿色”环保性。此外，智能功能应旨在通过响应结构周围环境的变化来提高基础设施的耐久性、回弹性和可持续性以实现其理想功能，从而使材料的行为方式更类似于某些生物材料。本文基于工程水泥基复合材料（ECC）的最新研究进展，提出可以设计出具有高性能兼智能多功能性的混凝土材料，并且其具有满足 21 世纪民用基础设施预期需求的潜力。本文重点介绍了 ECC 的相关特性以及未来研究的方向。

关键词： 高性能混凝土     多功能     智能     水泥基复合材料     耐久性     回弹性     可持续性     基础设施    

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Modern developments related to nanotechnology and nanoengineering of concrete

Konstantin SOBOLEV

《结构与土木工程前沿（英文）》 2016年 第10卷 第2期   页码 131-141 doi: 10.1007/s11709-016-0343-0

摘要： This paper reports on modern developments related to nanotechnology of cement and concrete. Recent advances in instrumentation and design of advanced nano-composite materials is discussed. New technological directions and historical milestones in nanoengineering and nanomodi?cation of cement-based materials are presented. It is concluded that there is a strong potential of nanotechnology to improve the performance of cement-based materials.

关键词： nanotechnology     cement     concrete     nanoparticle     nano-composite     nanomodification     carbon nanotubes     C-S-H gel     photocatalyst    

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Statistical modeling of radiolytic (

C. Padmanaban

《环境科学与工程前沿（英文）》 2019年 第13卷 第3期 doi: 10.1007/s11783-019-1126-3

摘要：

Linear, interactive and quadratic effects of process parameters were studied.

Degradation of Ofloxacin (Ofx) was related with G value of irradiation process.

The synergistic effect of H2O2 on lower dose of g-irradiation was established.

The process follows pseudo first order with dose constant (d = 0.232 kGy–1).

关键词： Ofloxacin     Gamma irradiation     Face centered central composite design     Reaction kinetics     Gas Chromatography-Mass spectrum    

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标题 作者 时间 类型 操作

A facile synthesis of high activity cube-like Pt/carbon composites for fuel cell application

Reza B. MOGHADDAM, Samaneh SHAHGALDI, Xianguo LI

期刊论文

Pt–C interactions in carbon-supported Pt-based electrocatalysts

期刊论文

Ionic liquid modified Pt/C electrocatalysts for cathode application in proton exchange membrane fuel

Huixin Zhang, Jinying Liang, Bangwang Xia, Yang Li, Shangfeng Du

期刊论文

Pt/C催化剂电子结构调控产氢介观动力学研究

陈文尧, 傅文钊, 段学志, 陈炳旭, 钱刚, 司锐, 周兴贵, 袁渭康, 陈德

期刊论文

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

期刊论文

Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

期刊论文

Valveless pumping using a two-stage impedance pump

C.-C. LEE, Y. A. ABAKR, K.-C. WOO

期刊论文

The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

期刊论文

Decoration of CdMoO micron polyhedron with Pt nanoparticle and their enhanced photocatalytic performance

期刊论文

NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

期刊论文

Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

期刊论文

potassium ion-responsive copolymer into polysulfone support membrane on the performance of thin-film composite

Meibo He, Zhuang Liu, Tong Li, Chen Chen, Baicang Liu, John C. Crittenden

期刊论文

高性能多功能水泥基复合材料

Victor C. Li

期刊论文

Modern developments related to nanotechnology and nanoengineering of concrete

Konstantin SOBOLEV

期刊论文

Statistical modeling of radiolytic (

C. Padmanaban

期刊论文