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Mahendra Yadav

Bio: Mahendra Yadav is an academic researcher from Banaras Hindu University. The author has contributed to research in topics: Catalysis & Tafel equation. The author has an hindex of 18, co-authored 32 publications receiving 1540 citations. Previous affiliations of Mahendra Yadav include P.G. College & Pacific Northwest National Laboratory.

Papers
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TL;DR: In this paper, the authors survey the research progress in hydrogen generation from liquid-phase chemical hydrogen storage materials and their regeneration, and present a review of these materials in hydrogen storage.
Abstract: In the search for future energy supplies, the application of hydrogen as an energy carrier is seen as a prospective issue. However, the implementation of a hydrogen economy is suffering from several unsolved problems. Particularly challenging is the storage of appropriate amounts of hydrogen. In this context one of the promising hydrogen storage techniques relies on liquid-phase chemical hydrogen storage materials, in particular, aqueous sodium borohydride, ammonia borane, hydrazine, hydrazine borane and formic acid. The use of these materials in hydrogen storage provides high gravimetric and volumetric hydrogen densities, low potential risk, and low capital investment because it is largely compatible with the current transport infrastructure. In this review, we survey the research progresses in hydrogen generation from these liquid-phase chemical hydrogen storage materials and their regeneration.

709 citations

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TL;DR: The resulting composites were investigated in the reduction of Cr(VI) to Cr(III) using formic acid, showing that the Pt and Pd catalysts were active with the Pt nanoparticles immobilized in MOF exhibiting the best performance.

195 citations

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TL;DR: In this paper, the first example of monometallic gold nanoparticles, functionalized with amine and encapsulated in silica nanospheres, was reported as a high-performance catalyst for hydrogen generation from aqueous formic acid for chemical hydrogen storage.
Abstract: We report the first example of monometallic gold nanoparticles, functionalized with amine and encapsulated in silica nanospheres, as a high-performance catalyst for hydrogen generation from aqueous formic acid for chemical hydrogen storage. Remarkably, the presence of amine in the silica sphere can make the gold nanoparticles highly active although the unsupported or silica-supported gold NPs being inactive for this reaction. The strong metal–molecular support interaction (SMMSI) could be extended, as a general strategy, to the development of nanocatalysts which need necessary environments around the active sites for a variety of catalytic reactions.

137 citations

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TL;DR: Palladium nanoparticles encapsulated within hollow silica nanospheres (Pd@SiO2) were synthesized using Pd(NH3)4Cl2 as precursor in a polyoxyethylene-nonylphenyl ether/cyclohexane reversed micelle system followed by NaBH4 reduction.
Abstract: Palladium nanoparticles (Pd NPs) encapsulated within hollow silica nanospheres (Pd@SiO2) (20–35 nm) were synthesized using Pd(NH3)4Cl2 as precursor in a polyoxyethylene-nonylphenyl ether/cyclohexane reversed micelle system followed by NaBH4 reduction. Pd NPs supported on silica nanospheres (Pd/SiO2) were prepared by the conventional impregnation of Pd(NH3)4Cl2 precursor to silica nanospheres, which were prepared using a similar reversed micelle system without Pd precursor, followed by NaBH4 reduction. The as-sythesized Pd@SiO2 and Pd/SiO2 catalysts have high catalytic activities, in comparison to Pd NPs supported on commercial silica, for the decomposition of formic acid at convenient temperature for chemical hydrogen storage. Remarkably, it has been observed that the interactions of the Pd nanoparticles with surface groups of silica supports are important for the catalytic performance.

81 citations

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TL;DR: In this article, a reverse-micelle method was used to synthesize core-shell structured Au-Co@SiO2 nanospheres, which showed better catalytic activity than that of Au-co@Si O2-RT.
Abstract: Core–shell structured Au-Co@SiO2 nanospheres have been synthesized using a reverse-micelle method. During heat treatment in vacuum, multiple Au-Co nanoparticles (NPs) embedded in SiO2 nanospheres (Au-Co@SiO2-RT) merged into single Au-Co NPs in SiO2 (Au-Co@SiO2-HT), resulting in a size increase of the Au-Co NPs. The Au-Co@SiO2-HT nanospheres showed better catalytic activity than that of Au-Co@SiO2-RT. The higher catalytic activity of Au-Co@SiO2-HT could be attributed to the decrease in the content of basic ammine by the decomposition of metal ammine complexes during the heat treatment. Compared with their monometallic counterparts, the bimetallic Au-Co NPs embedded in a SiO2 nanosphere show higher catalytic activity for the hydrolytic dehydrogenation of NH3BH3 to generate a stoichiometric amount of hydrogen at room temperature for chemical hydrogen storage. The synergistic effect between Au and Co inside the silica nanospheres plays an important role in the catalytic hydrolysis of NH3BH3.

78 citations


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TL;DR: This review provides an overview of the significant advances in the development of diverse MOF composites reported till now with special emphases on the synergistic effects and applications of the composites.
Abstract: Metal–organic frameworks (MOFs), also known as porous coordination polymers (PCPs), synthesized by assembling metal ions with organic ligands have recently emerged as a new class of crystalline porous materials. The amenability to design as well as fine-tunable and uniform pore structures makes them promising materials for a variety of applications. Controllable integration of MOFs and functional materials is leading to the creation of new multifunctional composites/hybrids, which exhibit new properties that are superior to those of the individual components through the collective behavior of the functional units. This is a rapidly developing interdisciplinary research area. This review provides an overview of the significant advances in the development of diverse MOF composites reported till now with special emphases on the synergistic effects and applications of the composites. The most widely used and successful strategies for composite synthesis are also presented.

1,738 citations

Journal Article
TL;DR: In this paper, the authors presented a method to detect the presence of a tumor in the human brain using EPFL-206025 data set, which was created on 2015-03-03, modified on 2017-05-12
Abstract: Note: Times Cited: 875 Reference EPFL-ARTICLE-206025doi:10.1021/cr0501846View record in Web of Science URL: ://WOS:000249839900009 Record created on 2015-03-03, modified on 2017-05-12

1,704 citations

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TL;DR: An overview of significant progress in the development of MNP/MOF composites, including various preparation strategies and characterization methods as well as catalytic applications is provided, with special emphasis on synergistic effects between the two components that result in an enhanced performance in heterogeneous catalysis.
Abstract: Metal–organic frameworks (MOFs), established as a relatively new class of crystalline porous materials with high surface area, structural diversity, and tailorability, attract extensive interest and exhibit a variety of applications, especially in catalysis. Their permanent porosity enables their inherent superiority in confining guest species, particularly small metal nanoparticles (MNPs), for improved catalytic performance and/or the expansion of reaction scope. This is a rapidly developing interdisciplinary research field. In this review, we provide an overview of significant progress in the development of MNP/MOF composites, including various preparation strategies and characterization methods as well as catalytic applications. Special emphasis is placed on synergistic effects between the two components that result in an enhanced performance in heterogeneous catalysis. Finally, the prospects of MNP/MOF composites in catalysis and remaining issues in this field have been indicated.

1,370 citations

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TL;DR: This review focuses on classifying different types of long wavelength absorbing BODIPY dyes based on the wide range of structural modification methods that have been adopted, and on tabulating their spectral and photophysical properties.
Abstract: This review focuses on classifying different types of long wavelength absorbing BODIPY dyes based on the wide range of structural modification methods that have been adopted, and on tabulating their spectral and photophysical properties. The structure–property relationships are analyzed in depth with reference to molecular modeling calculations, so that the effectiveness of the different structural modification strategies for shifting the main BODIPY spectral bands to longer wavelengths can be readily compared, along with their effects on the fluorescence quantum yield (ΦF) values. This should facilitate the future rational design of red/NIR region BODIPY dyes for a wide range of different applications.

1,013 citations