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[en] Interest in heterogeneous catalysis has increased dramatically in the last decade. The extent of interest in this and related field can be accessed from the newly coined terms like, ^semi-heterogeneous catalysis^, for the processes and mechanisms that are amalgam of homogeneous and heterogeneous catalysis. Whereas the progresses made I the area of science and technology of nano materials has provided the main impetus, the innovative processing of carbon nano tubes has added to potential applications in process engineering and consumer applications. The graphene based catalysts are yet another emerging class of catalysts with huge potential. This technical review summarizes the developments made in the area of material developments, a better understanding of processes involved and role of computational chemistry in the recent achievements. The emerging applications in the areas of process engineering have also been discussed. (author)

[en] Highlights: • Design of LDHs functionalized by 7-aminonaphthalene-1,3-disulfonic acid (LDHs@Propyl–ANDSA) as heterogeneous catalyst • Synthesis and characterization of LDHs@Propyl–ANDSA • Application of LDHs@Propyl–ANDSA in the synthesis of 7H-indeno[2,1-c]quinoline • Easy recovery and reuse of this catalyst without notable change in activity -- Abstract: The LDHs@Propyl-ANDSA was used as a new catalyst for synthesizing 7H-indeno[2,1-c]quinoline derivatives. The catalyst was integrated according to three-step synthesis. Zn-Cr layered double hydroxides (LDHs) were synthesized with molar ratio 2:1 by the co-precipitation method.

[en] In this communication we present a theoretical study of chemical reactions in a system of solid particles, immersed in a fluid environment. Our primary concern here is investigation of the systems of catalytic particles in a liquid media; however with some slight modifications our results are applicable to aerosol systems as well. We consider a second-order reaction, which proceeds both homogeneously in the environment, and heterogeneously at surfaces of catalyst particles. The Langmuir adsorption-desorption kinetics is considered explicitly. For definiteness, we are considering the so-called 'three-step mechanism' of the heterogeneous reaction.

[en] The lack of reproducibility of the cold fusion experiments, aggravated by the great diversity and inconsistency of the positive results, implies that these nuclear phenomena are hypersensitive, i.e., correlated to a open-quotes chaoticclose quotes factor. All the factors considered so far, such as structure, transformations, or defects of the crystal lattice; bubbles of deuterium; dendrites, etc., are insufficiently chaotic to explain the known facts. Experimental data suggest that nuclear reactions take place in active sites on the surface of the lattice, that they are stimulated by dynamics factors, and that they represent an extreme form of heterogeneous catalysis. Consequently, according to modern ideas concerning catalysis, the desired chaotic factor is the surface dynamics of some metallic deuterides (hydrides). This hypothesis, called the surfdyn concept, is compatible with all published data, explains the peculiarities of cold fusion, and must be supported by an adequate theory describing the nature and mechanisms of the different nuclear processes. 44 refs

[en] As a bourgeoning class of 2D materials, MXenes have recently attracted significant attention within heterogeneous catalysis for promoting reactions such as hydrogen evolution and C–H activation. However, the catalytic activity of MXenes is highly dependent on the structural configuration including termination groups and their distribution. Therefore, understanding the relation between the structure and the activity is desired for the rational design of MXenes as high-efficient catalysts. Here, we present that the correlation between the structure and activity of Ti₂CT₂ (T is a combination of O, OH and/or F) MXenes for C–H activation can be linked by a quantitative descriptor: the hydrogen affinity (E _H). A linear correlation is observed between the mean hydrogen affinity and the overall ratio of O terminations (x _O) in Ti₂CT₂ MXenes, in which hydrogen affinity increases as the x _O decreases, regardless to the species of termination groups. In addition, the hydrogen affinity is more sensitive to the presence of OH termination than F terminations. Moreover, the linear correlation between the hydrogen affinity and the activity of Ti₂CT₂ MXenes for C–H activation of both –CH₃ and –CH₂– groups can be extended to be valid for all three possible termination groups. Such a correlation provides fast prediction of the activity of general Ti₂CT₂ MXenes, avoiding tedious activation energy calculations. We anticipate that the findings have the potential to accelerate the development of MXenes for heterogeneous catalysis applications. (paper)

[en] A new cationic silver N-alkylpyridylporphyrin complex is able to ‘sense’ nanometric conductive particles with a diameter below 10 nm. The luminescence of the molecule changes its maximum from red to blue when it embraces a conductive (metallic or semiconducting) nanoparticle. The change is explained on the basis of a charge transfer between the molecule and the conductive nanoparticle along with a geometrical distortion of the porphyric ring and pyridinium substituents. This new molecule could be used to sense nanoparticle contamination in the environment, in the industry of heterogeneous catalysis and many other branches of nanometrological applications. (paper)

[en] Starting from the late seventies, the progressively increased availability of beamlines dedicated to X-ray absorption spectroscopy allowed the execution of experiments in chemistry. In this manuscript, I describe the contribution of Francois Garin at the frontier of heterogeneous catalysis and synchrotron radiation. Working at LURE as a scientific in charge of a beamline dedicated to X-ray absorption spectroscopy during almost twenty years and thus, having the opportunity to discuss with research groups working in heterogeneous catalysis in Europe as well as in the United States, it was quite easy to show that his work is clearly at the origin of current research in heterogeneous catalysis, not only in France, but in different synchrotron radiation centres. (authors)

[en] Selective H₂ production from formate with Pt nanoparticles dispersed by polyvinylpyrrolidone and cationic biopolymer, poly(L-lysine) (Pt-PVP/PLL), is attempted. Using Pt-PVP/PLL, the highly selective H₂ production based on formate decomposition was accomplished compared with that of Pt-PVP. Moreover, using Pt-PVP/poly(L-glutamic acid), anionic biopolymer, the catalytic activity for selective H₂ production based on formate decomposition was equivalent to that of Pt-PVP. This result suggests that the cationic site of PLL-captured formate ion and promoted the contact with the surface of Pt nanoparticles

[en] Nanoparticle sintering remains a fundamental problem in heterogeneous catalysis, motivating mechanistic studies toward mitigating deactivation of precious metal catalysts. We present a model based on the local coordination environment of metal atoms that can be used to provide total energy estimates for metal nanoparticles in a space of generic configurations. All energies are based only on a small set of density functional theory calculations of single metal atom adsorption on metal slabs. Here, a model that can provide accurate nanoparticle energies is an important step toward the goal of understanding their sintering behavior in practical catalytic contexts.