Search

Your search keyword '"Calvino, José J."' showing total 225 results
Start Over Author "Calvino, José J."
225 results on '"Calvino, José J."'

1. Ultrathin Washcoat and Very Low Loading Monolithic Catalyst with Outstanding Activity and Stability in Dry Reforming of Methane

Author

Agueniou, Fazia, Vidal, Hilario, Yeste, Maria Pilar, Hernandez-Garrido, Juan C., Cauqui, Miguel A., Rodriguez-Izquierdo, Jose M., Calvino, Jose J., and Gatica, Jose M.

Subjects
Condensed Matter - Materials Science
Abstract

A Ni/CeO2/ZrO2 catalyst with improved redox properties has been washcoated onto a honeycomb cordierite monolith in the form of a nonconventional alumina-catalyst layer, just a few nanometer thick. In spite of the very low active phase loading, the monolith depicts outstanding performance in dry reforming of methane, both in terms of activity, with values reaching the thermodynamic limit already at 750 C, even under extreme weight Hourly Space Velocities (WHSV 115-346 L.g-1.h-1), as well as in terms of stability during prolonged time on stream (TOS 24-48 h)., Comment: 7 pages, 3 figures, 19 references. Gold Open Access

Published
2024
Full Text
View/download PDF

2. An atomically efficient, highly stable and redox active Ce0.5Tb0.5Ox (3% mol.)/MgO catalyst for total oxidation of methane

Author

Sanchez, Juan J., Lopez-Haro, Miguel, Hernandez-Garrido, Juan C., Blanco, Ginesa, Cauqui, Miguel A., Rodríguez-Izquierdo, Jose M., Perez-Omil, Jose A., Calvino, Jose J., and Yeste, Maria P.

Subjects
Condensed Matter - Materials Science
Abstract

Redox and catalytic performance in total methane oxidation of a nonostructured ceria-terbia catalyst supported on magnesia is presented and compared to that of a pure ceria catalyst supported on MgO. The investigated material, Ce0.5Tb0.5Ox (3% mol.)/MgO, features several remarkable properties: a quite low total molar loading of the two lanthanide elements, high reducibility, as well as very high oxygen storage capacity al low temperatures and higher activity than MgO-supported ceria. In terms of lanthanide atomic content the catalytic performance of Ce0.5Tb0.5Ox (3% mol.)/MgO largely improves compared to that of bulk type ceria and ceria-magnesia solid solutions. Such a behavior implies proper optimization of the usage of lanthanide elements. A second contribution to atomic economy in the catalyst design relates to the fact that the new formulation demonstrate a stabilyty in the redox and catalytic performance against very high temperature treatments. An investigation on the structure of both the fresh and high-temperature-aged catalyst at the atomic scale by means of complementary aberration corrected microscopy techniques, reveals the ocuurrence of a variety of exotic, lanthanide-containing nanostructures, which span fron isolated, atomically dispersed Ln species to nonometer-sized CeTbO2-x patches, extended CeTbO2-x bilayers and 2D CeTbO2-x nanoparticles. Nanoanalytical results evidence the mixing of the two lanthanides at atomic levels in these nanostructures. The combined effects of nanostructuring, mixing of the lanthanides at the atomic level, and interaction with the MgO oxide are the roots of the improvement in funtional, redox and catalytic properties of the novel Ce0.5Tb0.5Ox (3% mol.)/MgO catalyst., Comment: 11 pages, eight figures, 3 tables, 60 references

Published
2024
Full Text
View/download PDF

3. Honeycomb monolithic design to enhance the performance of Ni-based catalysts for dry reforming of methane

Author

Agueniou, Fazia, Vidal, Hilario, Yeste, M. Pilar, Hernandez-Garrido, Juan C., Cauqui, Miguel A., Rodriguez-Izquierdo, Jose M., Calvino, Jose J., and Gatica, Jose M.

Subjects
Condensed Matter - Materials Science
Abstract

Supported Ni catalysts (4,5% wt%) using a Ce-Zr oxide (18/82 molar ratio and a ceria rich surface) depicting advanced redox properties, were deposited by washcoating over cordierite honeycombs (230 and 400 cpsi). FIB-STEM unveiled nanostructure details otherwise undistinguishable by conventional techniques. The catalytic performance was evaluated in the dry reforming of methane al 700-900 degree C, using a CH4:CO2 1:1 feddstock, and exploring high Weight Hourly Space Velocity (115-346 L.g-1.h-1). The structured catalyts exhibited better performance than the corresponding powers, reaching values close to rhermodynamics limits for booth reactants conversion and H2/CO ratio, from 750 dgree C, and no deactivation was observed in prolongued experiments (24-48 h). This was related to both the high catalytic efficiency after being deposited with low loading on the cordierite and the intrinsic advantages of the monolithic reactor, like preventing from the kinetic control that operates in powdered samples under high WHSV or limiting the deactivation., Comment: 10 pages, 8 figures, 3 tables, 61 references

Published
2024
Full Text
View/download PDF

14. Multicationic Sr4Mn3O10 mesostructures: molten salt synthesis, analytical electron microscopy study and reactivity

Author

González-Jiménez, Irma N., Torres-Pardo, Almudena, Rano, Simon, Laberty-Robert, Christel, Hernández-Garrido, Juan carlos, López-Haro, Miguel, Calvino, José J., Varela, Áurea, Sanchez, Clément, Parras, Marina, González-Calbet, José M., Portehault, David, González-Jiménez, Irma N., Torres-Pardo, Almudena, Rano, Simon, Laberty-Robert, Christel, Hernández-Garrido, Juan carlos, López-Haro, Miguel, Calvino, José J., Varela, Áurea, Sanchez, Clément, Parras, Marina, González-Calbet, José M., and Portehault, David

Abstract

Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Published
2024

16. Composite MAX phase/MXene/Ni electrodes with a porous 3D structure for hydrogen evolution and energy storage application

Author

Sergiienko, Sergii A., primary, Lajaunie, Luc, additional, Rodríguez-Castellón, Enrique, additional, Constantinescu, Gabriel, additional, Lopes, Daniela V., additional, Shcherban, Nataliya D., additional, Calvino, José J., additional, Labrincha, João A., additional, Sofer, Zdenek, additional, and Kovalevsky, Andrei V., additional

Published
2024
Full Text
View/download PDF

21. Quantitative, Spectro-kinetic Analysis of Oxygen in Electron-Beam Sensitive, Multimetallic Oxide Nanostructures

Author

López-Haro, Miguel, primary, Gómez-Recio, Isabel, additional, Pan, Huiyan, additional, Delgado, Juan J, additional, Chen, Xiaowei, additional, Cauqui, Miguel A, additional, Pérez-Omil, José A, additional, Ruiz-González, María L, additional, Hernando, María, additional, Parras, Marina, additional, González-Calbet, José M, additional, and Calvino, José J, additional

Published
2023
Full Text
View/download PDF

22. Understanding the potential-induced activation of a cobalt MOF electrocatalyst for the oxygen evolution reaction

Author

Universidad de Sevilla. Departamento de Química Física, Ministerio de Ciencia e Innovación (MICIN). España, Unión Europea (EU), Junta de Andalucía, Gutiérrez Tarriño, Silvia, Portorreal Bottier, Arismendy Antonio, Trasobares, Susana, Calvente Pacheco, Juan José, Calvino, José J., Olloqui Sariego, José Luis, Oña Burgos, Pascual, Universidad de Sevilla. Departamento de Química Física, Ministerio de Ciencia e Innovación (MICIN). España, Unión Europea (EU), Junta de Andalucía, Gutiérrez Tarriño, Silvia, Portorreal Bottier, Arismendy Antonio, Trasobares, Susana, Calvente Pacheco, Juan José, Calvino, José J., Olloqui Sariego, José Luis, and Oña Burgos, Pascual

Abstract

Metal–organic frameworks (MOFs) are attractive porous materials for electrocatalytic applications associated with carbon-free energy storage and conversion. This type of material usually requires a post-treatment to be used as electrocatalyst. The present work comprehensively investigates the electrochemical activation of a cobalt-MOF@Nafion composite that produces outstanding electrocatalytic performance for the water oxidation reaction at neutral pH. A detailed electrochemical characterization reveals that the electroactivation of the composite requires the participation of the oxygen evolution reaction (OER) and leads to a significant increase in the electroactive population of cobalt centers. It is shown that an increase of the applied activation potential in the OER region results in a faster electroactivation of the Co-MOF without affecting the intrinsic electrocatalytic properties of the active cobalt centers, as evidenced by the unique linear correlation between the electrocatalytic OER current and the population of electroactive cobalt. In addition, at structural level, it is shown that the electrochemical activation causes the partial disruption of the Nafion adlayer, as well as morphological changes of the Co–MOF particles from a compact, rounded morphology, before electrochemical activation, to a more open and expanded structure, after electroactivation; with the concomitant increase of the number of surface–exposed cobalt centers. Interestingly, these cobalt centers retain their coordinative chemistry and their laminar distribution in the nanosheets at the nanoscale, which is consistent with the preservation of their intrinsic electrocatalytic activity after potential–induced activation. In this scenario, these results suggest that only the electroactivated cobalt centers with good accessibility to the electrolyte are electrochemically active. This work provides a better understanding of the processes and structural changes underlying the electrochemica

Published
2023

28. The impact of Mn nonstoichiometry on the oxygen mass transport properties of La0.8Sr0.2Mn y O3±δthin films

Author

Chiabrera, Francesco M, primary, Baiutti, Federico, additional, Börgers, Jacqueline M, additional, Harrington, George F, additional, Yedra, Lluís, additional, Liedke, Maciej O, additional, Kler, Joe, additional, Nandi, Pranjal, additional, Sirvent, Juan de Dios, additional, Santiso, Jose, additional, López-Haro, Miguel, additional, Calvino, José J, additional, Estradé, Sonia, additional, Butterling, Maik, additional, Wagner, Andreas, additional, Peiró, Francesca, additional, De Souza, Roger A, additional, and Tarancón, Albert, additional

Published
2022
Full Text
View/download PDF

29. High Angle Liquid Cell TEM Tomography for In Situ Observation and 3D Reconstruction in Liquid

Author

Das, Partha Pratim, primary, Cookman, Jennifer, additional, Pérez, Alejandro Gómez, additional, Plana-Ruiz, Sergi, additional, López-Haro, Miguel, additional, Calvino, José J, additional, Casablanca, Jesús Gonzalez, additional, Grivas, Evangelos, additional, Antipas, Georgios SE, additional, Ntallis, Nikolaos A, additional, and Nicolopoulos, Stavros, additional

Published
2022
Full Text
View/download PDF

33. Silver Clusters of Five Atoms as Highly Selective Antitumoral Agents Through Irreversible Oxidation of Thiols (Adv. Funct. Mater. 29/2022)

Author

Porto, Vanesa, primary, Buceta, David, additional, Domínguez, Blanca, additional, Carneiro, Carmen, additional, Borrajo, Erea, additional, Fraile, María, additional, Davila‐Ferreira, Nerea, additional, Arias, Iria R., additional, Blanco, José M., additional, Blanco, Maria C., additional, Devida, Juan M., additional, Giovanetti, Lisandro J., additional, Requejo, Félix G., additional, Hernández‐Garrido, Juan C., additional, Calvino, José J., additional, López‐Haro, Miguel, additional, Barone, Giampaolo, additional, James, Andrew M., additional, García‐Caballero, Tomás, additional, González‐Castaño, Diego M., additional, Treder, Martin, additional, Huber, Wolfgang, additional, Vidal, Anxo, additional, Murphy, Michael P., additional, López‐Quintela, M. Arturo, additional, and Domínguez, Fernando, additional

Published
2022
Full Text
View/download PDF

34. Segmentation of scanning-transmission electron microscopy images using the ordered median problem

Author

Universidad de Sevilla. Departamento de Estadística e Investigación Operativa, Universidad de Sevilla. FQM331: Metodos y Modelos de la Estadistica y la Investigacion Operativa, Calvino, José J., López Haro, Miguel, Muñoz Ocaña, Juan M., Puerto Albandoz, Justo, Rodríguez Chía, Antonio Manuel, Universidad de Sevilla. Departamento de Estadística e Investigación Operativa, Universidad de Sevilla. FQM331: Metodos y Modelos de la Estadistica y la Investigacion Operativa, Calvino, José J., López Haro, Miguel, Muñoz Ocaña, Juan M., Puerto Albandoz, Justo, and Rodríguez Chía, Antonio Manuel

Abstract

This paper presents new models for segmentation of 2D and 3D Scanning-Transmission Electron Micro- scope images based on the ordered median function. The main advantage of using this function is its good adaptability to the different types of images to be studied due to the wide range of weight vec- tors that can be cast. Classical segmentation models stand out for their ability to provide a segmentation of the original image very quickly and with low computational burden. However, they do not usually achieve high quality segmentations with a small number of clusters in order to classify the different ele- ments which compose the structure represented in the image. The quality of the segmentation provided by our approach is analysed using different choices of the weight vector in some real instances. More- over, improvements are proposed for the formulations to reduce the computational time needed to solve these problems by taking advantage of the weight vector structure.

Published
2022

39. The impact of Mn nonstoichiometry on the oxygen mass transport properties of La0.8Sr0.2MnyO3±δ thin films

Author

Chiabrera, Francesco M., Baiutti, Federico, Börgers, Jacqueline Marie, Harrington, George F., Yedra, Lluís, Liedke, Maciej O., Kler, Joe, Nandi, Pranjal, Sirvent, Juan de Dios, Santiso, Jose, López-Haro, Miguel, Calvino, José J., Estradé, Sonia, Butterling, Maik, Wagner, Andreas, Peiró, Francesca, De Souza, Roger, and Tarancón, Albert

Subjects
perovskite oxides, cation nonstoichiometry, antisite defects, LSM, ddc:530
Abstract

JPhys energy 4(4), 044011 (2022). doi:10.1088/2515-7655/ac98df, Published by IOP Publishing, Bristol

Published
2022

42. Photocatalytic removal of benzene over Ti3C2Tx MXene and TiO2–MXene composite materials under solar and NIR irradiation

Author

Sergiienko, Sergii A., primary, Tobaldi, David M., additional, Lajaunie, Luc, additional, Lopes, Daniela V., additional, Constantinescu, Gabriel, additional, Shaula, Aliaksandr L., additional, Shcherban, Nataliya D., additional, Shkepu, Viacheslav I., additional, Calvino, José J., additional, Frade, Jorge R., additional, Labrincha, João A., additional, and Kovalevsky, Andrei V., additional

Published
2022
Full Text
View/download PDF

44. Exceptional Low-Temperature CO Oxidation over Noble-Metal-Free Iron-Doped Hollandites: An In-Depth Analysis of the Influence of the Defect Structure on Catalytic Performance

Author

Gómez-Recio, Isabel, primary, Pan, Huiyan, additional, Azor-Lafarga, Alberto, additional, Ruiz-González, María Luisa, additional, Hernando, María, additional, Parras, Marina, additional, Fernández-Díaz, María Teresa, additional, Delgado, Juan J., additional, Chen, Xiaowei, additional, Jiménez, Daniel Goma, additional, Portehault, David, additional, Sanchez, Clément, additional, Cabero, Mariona, additional, Martínez-Arias, Arturo, additional, González-Calbet, José M., additional, and Calvino, José J., additional

Published
2021
Full Text
View/download PDF

48. One-Step Encapsulation of ortho-Disulfides in Functionalized Zinc MOF. Enabling Metal-Organic Frameworks in Agriculture

Author

Mejías, Francisco J. R., Trasobares, Susana, Varela, Rosa M., Molinillo, José M. G., Calvino, José J., Macías, Francisco A., Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, and Química Orgánica

Subjects
weed control, Materials science, Surface Properties, chemistry.chemical_element, Capsules, One-Step, 02 engineering and technology, Zinc, 010402 general chemistry, 01 natural sciences, Crystallinity, herbicide, Lolium, General Materials Science, Disulfides, Particle Size, Metal-Organic Frameworks, MOF, Amaranthus, Aqueous solution, Molecular Structure, Herbicides, Chemical modification, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Bioavailability, Solubility, chemistry, Chemical engineering, Echinochloa, iDPC, Surface modification, encapsulation, Metal-organic framework, Agrochemicals, 0210 nano-technology, Research Article
Abstract

Application of natural products as new green agrochemicals with low average lifetime, low concentration doses, and safety is both complex and expensive due to chemical modification required to obtain desirable physicochemical properties. Transport, aqueous solubility, and bioavailability are some of the properties that have been improved using functionalized metal-organic frameworks based on zinc for the encapsulation of bioherbicides (ortho-disulfides). An in situ method has been applied to achieve encapsulation, which, in turn, led to an improvement in water solubility by more than 8 times after 2-hydroxypropyl-beta-cyclodextrin HP-beta-CD surface functionalization. High-resolution high-angle annular dark-field scanning transmission electron microscopy (HR HAADF-STEM) and integrated differential phase contrast (iDPC) imaging techniques were employed to verify the success of the encapsulation procedure and crystallinity of the sample. Inhibition studies on principal weeds that infect rice, corn, and potato crops gave results that exceed those obtained with the commercial herbicide Logran. This finding, along with a short synthesis period, i.e., 2 h at 25 degrees C, make the product an example of a new generation of natural-product-based herbicides with direct applications in agriculture., This work was financially supported by the "Ministerio de Economia y Competitividad" (Project AGL2017-88083-R), Spain. Furthermore, this work has received financial support from Junta de Andalucia (FQM334), MINECO/FEDER (Projects MAT2017-87579-R). This project has received funding from the European Union's Horizon 2020 research and innovation program under Grant 823717-ESTEEM3. STEM studies were performed at the DME Facilities of SCCYT of the University of Cadiz

Published
2021

49. Cobalt nanoclusters coated with N-doped carbon for chemoselective nitroarene hydrogenation and tandem reactions in water

Author

Ministerio de Economía y Competitividad (España), Gutiérrez-Tarriño, S., Rojas-Buzo, Sergio, Lopes, Christian W., Agostini, Giovanni, Calvino, José J., Corma, Avelino, Oña-Burgos, Pascual, Ministerio de Economía y Competitividad (España), Gutiérrez-Tarriño, S., Rojas-Buzo, Sergio, Lopes, Christian W., Agostini, Giovanni, Calvino, José J., Corma, Avelino, and Oña-Burgos, Pascual

Abstract

The development of active and selective non-noble metal-based catalysts for the chemoselective reduction of nitro compounds in aquo media under mild conditions is an attractive research area. Herein, the synthesis of subnanometric and stable cobalt nanoclusters, covered by N-doped carbon layers as core-shell (Co@NC-800), for the chemoselective reduction of nitroarenes is reported. TheCo@NC-800catalyst was prepared by the pyrolysis of the Co(tpy)complex impregnated on Vulcan carbon. In fact, the use of a molecular complex based on six N-Co bonds drives the formation of a well-defined and distributed cobalt core-shell nanocluster covered by N-doped carbon layers. In order to elucidate its nature, it has been fully characterized by using several advanced techniques. In addition, this as-prepared catalyst showed high activity, chemoselectivity and stability toward the reduction of nitro compounds with Hand under mild reaction conditions; water was used as a green solvent, improving the previous results based on cobalt catalysts. Moreover, theCo@NC-800catalyst is also active and selective for the one-pot synthesis of secondary aryl amines and isoindolinones through the reductive amination of nitroarenes. Finally, based on diffraction and spectroscopic studies, metallic cobalt nanoclusters with surface CoNpatches have been proposed as the active phase in theCo@NC-800material.

Published
2021

Catalog

Books, media, physical & digital resources
See catalog results