Playing with Structures at the Nanoscale: Designing Catalysts by Manipulation of Clusters and Nanocrystals as Building Blocks (original) (raw)
Creating and mastering nano-objects to design advanced catalytic materials
Coordination Chemistry Reviews, 2011
New developments in the synthesis of nano-materials have opened new possibilities for creating and mastering nano-objects in order to design novel advanced catalytic materials. This concise conceptual review will give a glimpse into this fast growing research area discussing some of the possibilities in this direction, the perspectives and the gap to reduce to develop selective catalysts for complex multistep reactions. Emphasis is given to the opportunities offered by a tailored nano-design of the catalysts, from exploiting nano-confinement effects and supramolecular active sites synergies in nano-reactors to the new possibilities offered by new concepts such as the reduction of the relaxation time between two consecutive turnover cycles on a single active site and forcing a vectorial active site sequence in complex, multistep reactions. Other aspects discussed include the development of hierarchic pore structure to maximize catalyst effectiveness, metal complexes confined with solid cavities and the concept of nano-reactors, nanostructured composites and ordered 1D-type metal oxides. It is shown how significant progress in nano-materials has still not corresponded with progress in understanding the relationship between nanostructure and catalytic performance and the development of a more general strategy on the design of next-generation nano-catalysts.
A Survey on Recent Developments in Catalysis Using Nanostructured Materials
This review describes that nanomaterials have received more attention by virtue of their excellent properties suited for applications in various fields such as electronic, pharmaceutical, biomedical, cosmetic, energy, and catalysis. Nanomaterial-based catalysts are usually heterogeneous catalysts. The extremely small size of the particles maximizes surface area exposed to the reactant, allowing more reactions to occur. However, thermal stability of these nanomaterials is limited by their critical sizes; the smaller the crystallite size, the lower thermal stability. The majority of industrial catalysts contain an active component in the form of nanoparticles smaller than 20nm in size that are dispersed onto high-surface-area supports. The importance of nanoparticles and nanostructure to the performance of catalysts has stimulated wide efforts to develop methods for their synthesis and characterization. Nanoparticles offer higher catalytic efficiency per gram than larger size materials due to their large surface-to-volume ratio. This makes them an attractive choice to use as catalysts. Indeed, catalysts are undoubtedly "the most successful current application of nanotechnology". In the first part of the paper, application of catalysis using nanostructured material in some reactions including alkylation, dehydrogenation, hydrogenation, Steam reforming of methane (SRM), carbon dioxide reforming (DRM), epoxidation of alkenes and oxidative coupling of methane to ethylene (OCM) are investigated. In the second part of the paper, properties of some chemical elements such as gold, silver, platinum, palladium, nickel and rhodium as nanocatalyst are studied. Our investigation shows that the metal nanoparticles can act as best catalyst for industrial application as these have large surface to volume ratio and have unique quantum size effect. Moreover, their homogeneous size distribution with the mean particle size is optimal for catalytic properties and also they increase conversion reactions. Finally, it is shown that despite some disadvantages in using nanostructured materials in catalysts such as high synthesis precise of them and also restriction in industrial usages, they have several prominent advantages which convince everyone to use nanomaterials as catalysts. In addition, this area of study is still interesting for researcher all over the world to extend application of nanostructured catalysis to all reactions which needs catalysts and also reduce synthesis price and solve other problems of using these kinds of catalysts in industrial applications.
Wiley eBooks, 2021
and the Spanish National Research Council. Prof. Garcia has been active in the field of heterogeneous catalysis working with zeolites, mesoporous materials, metal organic frameworks, graphene and nanoparticles, particularly supported gold nanoparticles. He has published over 600 papers and has filed over 25 patents, two of them in industrial exploitation. Prof. Garcia is the 2016 Rey D. Jaime I award in New technologies, Doctor Honoris Causa from the University of Bucharest and the recipient of the 2011 Janssen-Cilag award given by the Spanish Royal Society of Chemistry and the 2008 Alpha Gold of the Spanish Society of Glass and Ceramics.
Recent Progress in Synthesis of Nano-and Atomic-Sized Catalysts
Advanced Heterogeneous Catalysts Volume 1: Applications at the Nano-Scale, 2020
Well-defined nano-and atomic-sized heterogeneous catalysts with extremely high catalytic activities and unique selectivities show promise in addressing the critical energy-and environment-related challenges of this century. The exceptional properties of these catalysts, such as their electronic and geometric structures and the effective interactions between metals and supports, give rise to unprecedented catalytic efficiency over that of conventional catalysts. The facile prospects for tuning the active sites of these catalysts pave the way to optimizing their activities, selectivities, and stabilities, thus offering extensive application possibilities in significant industry-related catalytic reactions. A prerequisite for synthesizing nano-and atomic-sized catalyst is to prepare extremely disperse nano-and subnanoscale atoms on suitable supports. This book chapter summarizes various synthesis methods employed to synthesize nano-and atomic-scale catalysts.
Journal of Solid State Chemistry, 2008
The concept of nanocrystal conversion chemistry, which involves the use of pre-formed nanoparticles as templates for chemical transformation into derivative solids, has emerged as a powerful approach for designing the synthesis of complex nanocrystalline solids. The general strategy exploits established synthetic capabilities in simple nanocrystal systems and uses these nanocrystals as templates that help to define the composition, crystal structure, and morphology of product nanocrystals. This article highlights key examples of ''conversion chemistry'' approaches to the synthesis of nanocrystalline solids using a variety of techniques, including galvanic replacement, diffusion, oxidation, and ion exchange. The discussion is organized according to classes of solids, highlighting the diverse target systems that are accessible using similar chemical concepts: metals, oxides, chalcogenides, phosphides, alloys, intermetallic compounds, sulfides, and nitrides.
Application of new nanoparticle structures as catalysts: general discussion
Faraday discussions, 2018
Carlo Lamberti opened discussion of the paper by Chris-Kriton Skylaris: Do you think that your approach can be used also to investigate molecular absorption on the surface e.g. using CO as a probe? The coverage-dependent vibrational spectra of CO adsorbed on Pt and Pd nanoparticles (NP) are extremely rich in information and concern the progressive formation of three-fold bridged, two-fold bridged and linear CO adducts on diff erent (h, k, l) faces, usually (111) and (100). 1 -5 The complexity of such spectra contains coverage/size/shape-dependent information that has not been fully extracted so far. The creation, with your computational approach, of a huge library of coverage/size/shape dependent IR spectra, supported by a machine learning approach can potentially represent a breakthrough in the NP morphology determination.