Ordered nanoporous arrays of carbon supporting high dispersions of platinum nanoparticles

Joo, Sang Hoon; Choi, Seong Jae; Oh, Ilwhan; Kwak, Juhyoun; Liu, Zheng; Terasaki, Osamu; Ryoo, Ryong

doi:10.1038/35084046

Cited by 2,485 publications

(1,665 citation statements)

References 26 publications

Supporting

Mentioning

1,614

Contrasting

Unclassified

Order By: Relevance

“…This has been demonstrated to be crucial for the application of the nanosized Pt metal particles for a reaction under severe catalytic conditions. 41 4.2. Pt-C Contribution.…”

Section: Discussionmentioning

confidence: 99%

Metal Particle Size and Structure of the Metal−Support Interface of Carbon-Supported Platinum Catalysts as Determined with EXAFS Spectroscopy

et al. 2004

View full text Add to dashboard Cite

The metal particle size and structure of the metal-support interface of platinum supported on Vulcan XC-72 (a commercial catalyst used in platinum fuel-cell electrodes) and on carbon nanofibers (CNF) have been determined with extended X-ray absorption fine structure spectroscopy (EXAFS). The CNF-supported Pt catalysts were synthesized using a homogeneous deposition precipitation (HDP) method. The amount of acidic oxygen groups on the CNF surface was modified by treatment in an inert atmosphere at different temperatures. The average first shell Pt-Pt coordination number (∼5.5) detected in Pt/CNF is much smaller than for Pt/ Vulcan XC-72 (∼8.2). The presence of oxygen-containing groups in the CNF support most probably leads to the stabilization of small Pt particles on the CNF support. A prominent interaction between the metal particles and the support atoms was detected on both kinds of catalysts, which confirms that the metal is in direct contact with the carbon support atoms. After reduction, a long metal-carbon distance around 2.62 Å was detected in both Pt/Vulcan XC-72 and Pt/CNF. After evacuation of Pt/CNF at higher temperatures, the distance between support and interfacial metal atoms decreased to 2.02 Å. Therefore, the long metal-carbon support distance is ascribed to the presence of atomic chemisorbed hydrogen in the interface between the Pt particles and the carbon support. According to the number of interfacial Pt-C bonds (four), the platinum particles supported on CNF are proposed to be in contact with a prismatic surface of the carbon support, on which oxygen groups have more stable bonds with carbon atoms. Six Pt-C bonds could be detected in the metal-support interface of Pt/Vulcan XC-72 with an even longer carbon shell at 3.62 Å, indicating that the metal particles are located on a more carbon-rich surface. This supports a structural model in which the platinum metal particles are epitaxially grown on the (0001) basal surface plane of carbon graphite.

show abstract

“…This has been demonstrated to be crucial for the application of the nanosized Pt metal particles for a reaction under severe catalytic conditions. 41 4.2. Pt-C Contribution.…”

Section: Discussionmentioning

confidence: 99%

Metal Particle Size and Structure of the Metal−Support Interface of Carbon-Supported Platinum Catalysts as Determined with EXAFS Spectroscopy

et al. 2004

View full text Add to dashboard Cite

show abstract

“…8 Recently, various types of ordered mesoporous carbons (OMCs) have been generated via a multistep synthetic procedure, in which ordered mesoporous silicas (OMSs) are employed as hard templates. [9][10][11][12][13][14][15] The most common synthetic route yielding OMCs involves preparation of OMS templates, impregnation of the OMS pores with carbon precursors, carbonization, and removal of the templates ( Fig. 1(A)).…”

mentioning

confidence: 99%

Synthesis of ordered mesoporous carbons with channel structure from an organic–organic nanocomposite

et al. 2005

View full text Add to dashboard Cite

Mesoporous carbons with ordered channel structure (COU-1) have been successfully fabricated via a direct carbonization of an organic-organic nanocomposite.The discovery of nanostructured carbon materials such as fullerenes 1 and carbon nanotubes 2 has led to a considerable interest in the development of various carbonaceous materials. In particular, porous carbonaceous materials have been attracting much attention because of their high surface areas, large pore volumes, chemical inertness and high mechanical stability. Porous carbons show promise in the fields of hydrogen-storage, catalysis and electrochemistry. Many researchers have reported control of such pore structures through the template method, using various inorganic porous materials such as alumina membranes, 3 zeolites, 4-6 siliceous opals 7 and silica xerogels. 8 Recently, various types of ordered mesoporous carbons (OMCs) have been generated via a multistep synthetic procedure, in which ordered mesoporous silicas (OMSs) are employed as hard templates. [9][10][11][12][13][14][15] The most common synthetic route yielding OMCs involves preparation of OMS templates, impregnation of the OMS pores with carbon precursors, carbonization, and removal of the templates ( Fig. 1(A)). The removal of the OMS templates can be performed through a treatment with HF solution, converting the carbon into a porous form, while retaining the nanostructural features of the OMSs.In contrast, our novel OMC synthesis route, reported here, avoids the use of hard templates, and could thus reduce the number of preparation steps and the cost involved in producing these materials. Our strategy is to use an organic-organic interaction between a thermosetting polymer and a thermallydecomposable surfactant to form a periodic ordered nanocomposite. The thermosetting polymer is carbonized by heating under N 2 , after which process it remains as a carbonaceous pore wall ( Fig. 1(B)). Resorcinol/formaldehyde (RF) and triethyl orthoacetate (EOA) were used as the carbon co-precursors and triblock copolymer Pluronic F127 was used as a surfactant (Fig. 1(C)). The resultant materials are referred to as COU-1.In a typical synthesis, 0.661 g resorcinol was completely dissolved in a mixture composed of 1.74 g deionized water, 2.3 g ethanol and 0.06 ml hydrochloric acid (5 mol l 21 ). Then, 0.378 g Pluronic F127 was added to the resorcinol solution. After the complete dissolution of the Pluronic F127, 0.487 g of triethyl orthoacetate and 0.541 g of formaldehyde was added to the solution, and stirred at 30 uC for 20 min. The resultant solution was added dropwise to a silicon substrate spinning at 50 rpm, and then the substrate was spun up to 1000 rpm for 2 min. For polymerization of the resorcinol with formaldehyde, the asdeposited sample was heated at 90 uC for 5 h, in air. Then, the resultant brown deposit was carbonized under a nitrogen atmosphere at 400 uC for 3 h at a heating rate of 1 uC min 21 , followed by further carbonization at 600 and 800 uC for 3 h.{ Electronic supplementary informati...

show abstract

“…[5][6][7][8] After enormous efforts have been devoted to this field in recent years, the pore structures of carbons at micropore or mesopore levels can be readily controllable via various synthesis approaches. [9][10][11] Recently, porous carbon-metal oxide composite materials have attracted huge interest due to their promising potential in environmental applications, such as gas sorption and contamination removal from water.…”

Section: Introductionmentioning

confidence: 99%

Atomically homogeneous dispersed ZnO/N-doped nanoporous carbon composites with enhanced CO2 uptake capacities and high efficient organic pollutants removal from water

Chen

Kong

et al. 2015

Carbon

View full text Add to dashboard Cite

Advanced functional composite of ZnO nanoparticles embedded in N-doped nanoporous carbons has been synthesized by a simple one-step carbonization of zeolitic imidazolate framework-8 under a water stream atmosphere. A variety of characterization techniques show that the introduction of water steam during the carbonization process holds the key to obtain the fine and homogeneously dispersed ZnO nanoparticles within the functionalised nanoporous carbon matrix. Possessing a higher specific surface area, a larger pore volume and abundant oxygen-containing hydrophilic functional groups, the resulting composite exhibits a stronger interaction with CO 2 and is more efficient to promote the photocatalytic degradation-adsorption of methylene blue under visible light than the composite obtained without steam treatment. As a result, the steam derived composite exhibits increased CO 2 uptake capacity and excellent methylene blue molecules removal from water. Using different metal-organic frameworks as precursors, this new, simple and green method can be further expanded to generate various new homogeneous dispersed functional metal oxide/porous carbon composites with high efficient in relevant applications.

show abstract

Ordered nanoporous arrays of carbon supporting high dispersions of platinum nanoparticles

Cited by 2,485 publications

References 26 publications

Metal Particle Size and Structure of the Metal−Support Interface of Carbon-Supported Platinum Catalysts as Determined with EXAFS Spectroscopy

Metal Particle Size and Structure of the Metal−Support Interface of Carbon-Supported Platinum Catalysts as Determined with EXAFS Spectroscopy

Synthesis of ordered mesoporous carbons with channel structure from an organic–organic nanocomposite

Atomically homogeneous dispersed ZnO/N-doped nanoporous carbon composites with enhanced CO2 uptake capacities and high efficient organic pollutants removal from water

Contact Info

Product

Resources

About