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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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THE 4C APPROACH AS A WAY TO UNDERSTAND SPECIES INTERACTIONS DETERMINING INTERCROPPING PRODUCTIVITY

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 387-399 doi: 10.15302/J-FASE-2021414

摘要：

Modern agriculture needs to develop transition pathways toward agroecological, resilient and sustainable farming systems. One key pathway for such agroecological intensification is the diversification of cropping systems using intercropping and notably cereal-grain legume mixtures. Such mixtures or intercrops have the potential to increase and stabilize yields and improve cereal grain protein concentration in comparison to sole crops. Species mixtures are complex and the 4C approach is both a pedagogical and scientific way to represent the combination of four joint effects of Competition, Complementarity, Cooperation, and Compensation as processes or effects occurring simultaneously and dynamically between species over the whole cropping cycle. Competition is when plants have fairly similar requirements for abiotic resources in space and time, the result of all processes that occur when one species has a greater ability to use limiting resources (e.g., nutrients, water, space, light) than others. Complementarity is when plants grown together have different requirements for abiotic resources in space, time or form. Cooperation is when the modification of the environment by one species is beneficial to the other(s). Compensation is when the failure of one species is compensated by the other(s) because they differ in their sensitivity to abiotic stress. The 4C approach allows to assess the performance of arable intercropping versus classical sole cropping through understanding the use of abiotic resources.

 

关键词： compensation     competition     complementarity     cooperation     interspecific interactions     land equivalent ratio     light     nutrients     species mixtures     water    

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Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton exchange membrane fuel cells

《能源前沿（英文）》 doi: 10.1007/s11708-023-0907-3

摘要： Platinum (Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). However, their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading reduction. Based on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts, Pt single-atom catalysts (Pt SACs) as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this paper. The design thoughts and synthesis of various isolated, alloyed, and nanoparticle-contained Pt SACs are summarized. The single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the catalysts. To advance further research and development of Pt SACs for viable implementation in PEMFCs, various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis     Pt single-atom catalysts     conventional Pt-based catalysts     design thoughts and synthesis     metal-support interactions    

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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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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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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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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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A Bayesian modeling approach to bi-directional pedestrian flows in carnival events

C. WONG, William H. K. LAM

《工程管理前沿（英文）》 2017年 第4卷 第4期   页码 483-489 doi: 10.15302/J-FEM-2017023

摘要： Bi-directional pedestrian flows are common at crosswalks, footpaths, and shopping areas. However, the properties of pedestrian movement may vary in urban areas according to the type of walking facility. In recent years, crowd movements at carnival events have attracted the attention of researchers. In contrast to pedestrian behavior in other walking facilities, pedestrians whose attention is attracted by carnival displays or activities may slow down and even stop walking. The Lunar New Year Market is a traditional carnival event in Hong Kong held annually one week before the Lunar New Year. During the said event, crowd movements can be easily identified, particularly in Victoria Park, where the largest Lunar New Year Market in Hong Kong is hosted. In this study, we conducted a video-based observational survey to collect pedestrian flow and speed data at the Victoria Park Lunar New Year Market on the eve of the Lunar New Year. Using the collected data, an extant mathematical model was calibrated to capture the relationships between the relevant macroscopic quantities, thereby providing insight into pedestrian behavior at the carnival event. Bayesian inference was employed to calibrate the model by using prior data obtained from a previous controlled experiment. Results obtained enhance our understanding of crowd behavior under different conditions at carnival events, thus facilitating the improvement of the safety and efficiency of similar events in the future.

关键词： pedestrian flow model     bi-directional interactions     empirical studies     Bayesian inference    

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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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The modification of titanium in mesoporous silica for Co-based Fischer–Tropsch catalysts

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1224-1236 doi: 10.1007/s11705-022-2139-1

摘要： Ordered SBA-15 mesoporous silica with incorporated titanium was successfully synthesized via a one-pot hydrothermal crystallization method. The characterization including powder X-ray diffraction, Brunauer–Emmett–Teller, transmission electron microscope, temperature-programmed reduction, temperature-programmed desorption, Fourier transform infrared and ultraviolet-visible-near infrared spectrometer was performed to explore the physical and chemical structures of both the supports and the catalysts. The results showed that titanium was successfully incorporated into the mesoporous silica framework with a limited amount of titanium (Si/Ti > 20), and the mesoporous structure was retained. However, the increased titanium content inevitably resulted in the formation of anatase TiO 2 particles on the support surface. The increased incorporated titanium strengthened the interactions between cobalt species and supports, which was favorable for the cobalt species dispersion, despite the limited cobalt oxide reducibility. The enhanced metal-support interactions were beneficial for the CO/H2 ratio at the active cobalt sites, which facilitated the formation of more C5+ hydrocarbons. This study provides a promising method for support modification with incorporated-heteroatoms for the rational development of Fischer–Tropsch catalysts.

关键词： Fischer–Tropsch synthesis     titanium incorporation     mesoporous silica     metal-support interactions     C5+ selectivity    

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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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Responses of microbial interactions to elevated salinity in activated sludge microbial community

《环境科学与工程前沿（英文）》 2023年 第17卷 第5期 doi: 10.1007/s11783-023-1660-x

摘要：

● Salinity led to the elevation of NAR over 99.72%.

关键词： Elevated salinity     Activated sludge system     Pollution removal     Microbial interactions     Competitive relationship    

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Concentrations of anthropogenic Pt and Pd in urban roadside soils in Xuzhou, China

WANG Xuesong, SUN Cheng

《环境科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 475-479 doi: 10.1007/s11783-008-0071-3

摘要： The potential accumulation of platinum group elements (PGE) in the environment from automobile catalysts is high in urban areas, with the major sinks being roadside soils. Therefore, this investigation presented the detailed study on characterized concentrations of Pt and Pd and their enrichment ratios in urban roadside soils in Xuzhou, China in March 2003. Data from 21 roadside topsoil samples analyzed by inductively coupled plasma-mass spectrometer (ICP-MS) illustrated that the medians of concentrations of Pt and Pd were 2.9 and 2.8 ng/g, respectively. Hierarchical clustering analysis indicated that Pt and Pd were mainly from traffic emissions. Compared to unpolluted soils, computation of Pt and Pd enrichment ratios suggested that the Xuzhou roadside soils had average enrichment factors of 3.53 for Pt (in range of 1.22–5.73) and of 3.37 for Pd (in range of 1.35–4.46). Lower Pt/Pd ratios (in range of 0.35–2.86) in relation to similar studies in other countries were observed, which might be due to the different Pt/Pd ratios in Chinese automobile catalytic converters. Moreover, fine fraction (<250 ?m) contained higher concentrations of Pt and Pd compared to the coarse fraction (250–500 ?m).

关键词： platinum     detailed     different     Hierarchical     automobile catalytic    

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Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 298-304 doi: 10.1007/s11705-009-0019-6

摘要： We investigated the effect of HMT (hexamethylenetetraamine) on the anodic growth of TiO nanotube arrays. The tube length increases to 4.3 μm with HMT concentration increasing to 0.04 mol·L . Adsorption of HMT on the TiO surface is shown to markedly decrease the chemical dissolution rate of tube mouth, resulting in longer nanotube length. Furthermore, Pt nanoparticles were successfully deposited on the surface of TiO nanotubes by ac electrodeposition method. The TiO /Pt composites were characterized by field emission scanning electron microscope (FESEM), X-ray photoelectron spectra (XPS), and photoelectrochemistry. An enhancement in photocurrent density has been achieved upon modification of TiO nanotubes with Pt nanoparticles.

关键词： TiO2 nanotube arrays     HMT     TiO2/Pt     Photocurrent density    

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标题 作者 时间 类型 操作

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

期刊论文

THE 4C APPROACH AS A WAY TO UNDERSTAND SPECIES INTERACTIONS DETERMINING INTERCROPPING PRODUCTIVITY

期刊论文

Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton exchange membrane fuel cells

期刊论文

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

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

Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

期刊论文

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

期刊论文

A Bayesian modeling approach to bi-directional pedestrian flows in carnival events

C. WONG, William H. K. LAM

期刊论文

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

期刊论文

The modification of titanium in mesoporous silica for Co-based Fischer–Tropsch catalysts

期刊论文

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

Zhong HE,Xianqin WANG

期刊论文

Responses of microbial interactions to elevated salinity in activated sludge microbial community

期刊论文

Concentrations of anthropogenic Pt and Pd in urban roadside soils in Xuzhou, China

WANG Xuesong, SUN Cheng

期刊论文

Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

期刊论文