Experimental methods in chemical engineering: Temperature programmed surface reaction spectroscopy—<scp>TPSR</scp>

Jehng, Jih‐Mirn; Wachs, Israel E.; Patience, Gregory S.; Dai, Yong‐Ming

doi:10.1002/cjce.23913

Cited by 11 publications

(8 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This approach is usually achieved by measurements based on temperature-programmed desorption (TPD) and temperature-programmed surface reaction (TPSR). 216 For instance, the reactivities of bimetallic nanoclusters generated by physical approaches such as size-selection method are mostly measured by these techniques. For instance, the TPD data for methanol adsorbed on the surface of AuPt clusters supported on TiO 2 (110) surface can not only indicate the reactivity of the AuPt clusters, but also provide insights on the exposed surface sites of the bimetallic clusters according to the variation of the desorption temperature and the final products.…”

Section: Characterizations Of Surface Reactivitymentioning

confidence: 99%

Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles

2023

View full text Add to dashboard Cite

Heterogeneous bimetallic catalysts have broad applications in industrial processes, but achieving a fundamental understanding on the nature of the active sites in bimetallic catalysts at the atomic and molecular level is very challenging due to the structural complexity of the bimetallic catalysts. Comparing the structural features and the catalytic performances of different bimetallic entities will favor the formation of a unified understanding of the structure−reactivity relationships in heterogeneous bimetallic catalysts and thereby facilitate the upgrading of the current bimetallic catalysts. In this review, we will discuss the geometric and electronic structures of three representative types of bimetallic catalysts (bimetallic binuclear sites, bimetallic nanoclusters, and nanoparticles) and then summarize the synthesis methodologies and characterization techniques for different bimetallic entities, with emphasis on the recent progress made in the past decade. The catalytic applications of supported bimetallic binuclear sites, bimetallic nanoclusters, and nanoparticles for a series of important reactions are discussed. Finally, we will discuss the future research directions of catalysis based on supported bimetallic catalysts and, more generally, the prospective developments of heterogeneous catalysis in both fundamental research and practical applications.

show abstract

Section: Characterizations Of Surface Reactivitymentioning

confidence: 99%

Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles

2023

View full text Add to dashboard Cite

show abstract

Section: Applicationsmentioning

confidence: 99%

“…These three techniques address the molecular level changes and reactivity (bottom rows of Figures 9 and 10), but MÖS has been less successful integrating operando versus the other two. [22] VOSViewer online software builds word maps based on bibliometric data indexed by WoS and Scopus. It grouped the 100 most mentioned keywords of the 3000 articles published in 2018, 2019, and 2020 into six clusters (Figure 11).…”

Section: Applicationsmentioning

confidence: 99%

Experimental methods in chemical engineering: Mössbauer spectroscopy

Bianchi

Djellabi

Ponti³

et al. 2021

Can J Chem Eng

Self Cite

View full text Add to dashboard Cite

When a free nucleus absorbs or emits a gamma ray, it recoils to conserve energy, just like a gun recoils after shooting a bullet. Nuclei bound to a crystal lattice conserve energy when they absorb or emit gamma rays from a nuclear transition as they are fixed so their movement is restricted. This restriction is recoilless nuclear resonance fluorescence-the Mössbauer effect. The energy transmitted through a sample reveals its electronic and molecular structure and magnetic properties but only when the atoms in the source and sample are the same isotope-57 Co/ 57 Fe is the most common couple. So, many of its applications are to identify iron species or how they change as a function of environmental conditions, like corrosion. A bibliometric map identified six major clusters centred around: nanoparticles and magnetite (Fe 3 O 4 ), crystal structure and spectroscopy, oxidation and catalysis, X-ray diffraction (XRD) and Raman spectroscopy, 57 Fe and cathodes, and Co and thin films. In the last 30 years, the number of articles per year that mention the technique has hovered around 1250. More recently, Mössbauer spectroscopy has experienced a great rediscovery, particularly in the industrial sector for the solution of some problems, but also in space exploration.

show abstract

“…Temperature programmed surface reaction is a more advanced technique that applies probe molecules to assess surface actives sites, reaction mechanisms, and kinetics rates. [39,40] In-situ Raman spectroscopy coupled with TP (TP-Raman) adds the capability to examine molecular structures and identify active phases (and thus mechanism). In-situ TPR-Raman studies include alumina-supported chromium catalysts, which are active for alkane dehydrogenation, ethane polymerization, and NOx selective reduction.…”

Section: Tp-ramanmentioning

confidence: 99%

Experimental methods in chemical engineering: Raman spectroscopy

2020

Self Cite

View full text Add to dashboard Cite

When photons impinge on a substrate, most scatter with the same frequency (elastic scattering or Rayleigh dispersion) and only 10 −7 scatter with a different energy (inelastic scattering). This inelastic interaction (Raman scattering) exchanges energy in the region of molecular vibrational transitions for crystalline and amorphous materials. Raman bands in a spectra represent vibrational transitions, like infrared, however the selection rules are different. Typically, the vibrations that are intense in Raman are weak in infrared and vice versa. A remarkable feature of the Raman effect is that it is highly sensitive to nanocrystals, even below 4 nm, which are too small to generate XRD patterns. Plasmonic enhancement, like surface-enhanced Raman spectroscopy (SERS) boost the Raman signal by 10 4 , providing single-molecule detection capability. Glass, quartz, and sapphire are transparent to Raman effect (depending on the energy of the incident excitation radiation), which makes it ideal to examine materials under reaction conditions (in-situ cells and operando reactors that operate over a broad range of temperature, pressures, and environments). Raman spectroscopy emerged in the 1930s; however, infrared spectrometry displaced it. With the advent of powerful lasers in the 1970s, more researchers began to apply Raman routinely. In 2019, the Web of Science indexed 20 400 articles mentioning Raman against 50 000 articles mentioning infrared. Chemical engineers apply Raman less frequently than in material science, physical chemistry, and applied physics, with 887 articles vs 6250, 3700, and 3510 for the other disciplines. A bibliometric analysis identified four research clusters centred on thin films and optics, graphene and nanocomposites, nanoparticles and SERS, and photocatalyst. K E Y W O R D S operando, Raman, Rayleigh, Stokes bands, surface enhanced Raman spectroscopy 1 | INTRODUCTION Raman spectroscopy has become an important and popular analytical tool since it is non-destructive and identifies molecular structure properties and how they change under reactive environments. The technique is based on the Raman effect that C.V. Raman described in 1928 [1] : when electromagnetic radiation (typically monochromatic laser light; near ultraviolet, visible, or near infrared) interacts with a materials molecular vibrations, the incident energy of the photons are scattered with a predominantly lower energy (inelastic scattering). However,

show abstract

Experimental methods in chemical engineering: Temperature programmed surface reaction spectroscopy—TPSR

Cited by 11 publications

References 36 publications

Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles

Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles

Experimental methods in chemical engineering: Mössbauer spectroscopy

Experimental methods in chemical engineering: Raman spectroscopy

Contact Info

Product

Resources

About