A Highly Active Star Decahedron Cu Nanocatalyst for Hydrocarbon Production at Low Overpotentials

The electrochemical carbon dioxide reduction reaction (CO_2RR) presents a viable approach to recycle CO_2 gas into low carbon fuels. Thus, the development of highly active catalysts at low overpotential is desired for this reaction. Herein, a high‐yield synthesis of unique star decahedron Cu nanoparticles (SD‐Cu NPs) electrocatalysts, displaying twin boundaries (TBs) and multiple stacking faults, which lead to low overpotentials for methane (CH_4) and high efficiency for ethylene (C_2H_4) production, is reported. Particularly, SD‐Cu NPs show an onset potential for CH_4 production lower by 0.149 V than commercial Cu NPs. More impressively, SD‐Cu NPs demonstrate a faradaic efficiency of 52.43% ± 2.72% for C_2H_4 production at −0.993 ± 0.0129 V. The results demonstrate that the surface stacking faults and twin defects increase CO binding energy, leading to the enhanced CO_2RR performance on SD‐Cu NPs

Presión arterial del recién nacido de madres preeclámpticas eclámpticas Hospital Regional de Cajamarca 2016

La presión arterial del recién nacido está sujeta a variaciones por diversas causas entre ellas la patología materna conocida como la preeclampsia El objetivo de la presente investigación fue determinar y analizar la presión arterial durante las primeras en las primeras 36 horas de vida, en forma periódica, de los recién nacidos hijos de madres preeclámpticas y la presión arterial de los recién nacidos hijos de madres no preeclámpticas, atendidos en el Hospital Regional de Cajamarca durante los meses de enero- febrero del año 2016. El estudio fue de tipo descriptivo, comparativo, correlacional, no experimental, de corte transversal y naturaleza prospectiva. Se incluyeron a 75 recién nacidos, hijos de madres preeclámpticas, y 75 recién nacidos de madres no preeclámpticas que cumplían con los criterios de inclusión y exclusión, atendidos en el Hospital Regional de Cajamarca durante los meses de enero y febrero del año 2016. Se realizaron mediciones de presión arterial en tres ocasiones: 12, 24 y 36 horas de nacimiento. Los resultados encontrados en la presente investigación fueron: edad materna promedio de 28.5 años, en gran porcentaje multíparas (49% y 48% en ambos grupos) y la mayoría con el diagnóstico de preeclampsia severa (52%). Los neonatos nacieron predominantemente por vía vaginal (56% y 86,8%), a término (76% y 94,7%), de sexo masculino con un porcentaje de 54,7% en el primer grupo y sexo femenino en el segundo grupo con 42%; con peso y talla al nacer promedio de 3026.7 gramos y 49.2 centímetros, respectivamente, con un puntaje de Apgar en su mayoría de 8 al minuto y 9 a los cinco minutos, con una cantidad mínima de neonatos con administración prenatales de corticoides (0,7%). Se determinó que la presión arterial se incrementó en las primeras 12 horas de vida en los recién nacidos de madres preeclámpticas, regularizándose, la mayoría, a las 36 horas, continuando elevada en un buen porcentaje (30,7%). En cuanto a los recién nacidos de madres no preeclámpticas una considerable cantidad tuvo presión arterial normal y los que tuvieron presión arterial alta en las primeras horas, se regularizaron a las 36 horasTesi

A Highly Active Star Decahedron Cu Nanocatalyst for Hydrocarbon Production at Low Overpotentials

The electrochemical carbon dioxide reduction reaction (CO_2RR) presents a viable approach to recycle CO_2 gas into low carbon fuels. Thus, the development of highly active catalysts at low overpotential is desired for this reaction. Herein, a high‐yield synthesis of unique star decahedron Cu nanoparticles (SD‐Cu NPs) electrocatalysts, displaying twin boundaries (TBs) and multiple stacking faults, which lead to low overpotentials for methane (CH_4) and high efficiency for ethylene (C_2H_4) production, is reported. Particularly, SD‐Cu NPs show an onset potential for CH_4 production lower by 0.149 V than commercial Cu NPs. More impressively, SD‐Cu NPs demonstrate a faradaic efficiency of 52.43% ± 2.72% for C_2H_4 production at −0.993 ± 0.0129 V. The results demonstrate that the surface stacking faults and twin defects increase CO binding energy, leading to the enhanced CO_2RR performance on SD‐Cu NPs

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Taking the pulse of Earth's tropical forests using networks of highly distributed plots

Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests.Additional co-authors: Susan Laurance, William Laurance, Francoise Yoko Ishida, Andrew Marshall, Catherine Waite, Hannsjoerg Woell, Jean-Francois Bastin, Marijn Bauters, Hans Beeckman, Pfascal Boeckx, Jan Bogaert, Charles De Canniere, Thales de Haulleville, Jean-Louis Doucet, Olivier Hardy, Wannes Hubau, Elizabeth Kearsley, Hans Verbeeck, Jason Vleminckx, Steven W. Brewer, Alfredo Alarcón, Alejandro Araujo-Murakami, Eric Arets, Luzmila Arroyo, Ezequiel Chavez, Todd Fredericksen, René Guillén Villaroel, Gloria Gutierrez Sibauty, Timothy Killeen, Juan Carlos Licona, John Lleigue, Casimiro Mendoza, Samaria Murakami, Alexander Parada Gutierrez, Guido Pardo, Marielos Peña-Claros, Lourens Poorter, Marisol Toledo, Jeanneth Villalobos Cayo, Laura Jessica Viscarra, Vincent Vos, Jorge Ahumada, Everton Almeida, Jarcilene Almeida, Edmar Almeida de Oliveira, Wesley Alves da Cruz, Atila Alves de Oliveira, Fabrício Alvim Carvalho, Flávio Amorim Obermuller, Ana Andrade, Fernanda Antunes Carvalho, Simone Aparecida Vieira, Ana Carla Aquino, Luiz Aragão, Ana Claudia Araújo, Marco Antonio Assis, Jose Ataliba Mantelli Aboin Gomes, Fabrício Baccaro, Plínio Barbosa de Camargo, Paulo Barni, Jorcely Barroso, Luis Carlos Bernacci, Kauane Bordin, Marcelo Brilhante de Medeiros, Igor Broggio, José Luís Camargo, Domingos Cardoso, Maria Antonia Carniello, Andre Luis Casarin Rochelle, Carolina Castilho, Antonio Alberto Jorge Farias Castro, Wendeson Castro, Sabina Cerruto Ribeiro, Flávia Costa, Rodrigo Costa de Oliveira, Italo Coutinho, John Cunha, Lola da Costa, Lucia da Costa Ferreira, Richarlly da Costa Silva, Marta da Graça Zacarias Simbine, Vitor de Andrade Kamimura, Haroldo Cavalcante de Lima, Lia de Oliveira Melo, Luciano de Queiroz, José Romualdo de Sousa Lima, Mário do Espírito Santo, Tomas Domingues, Nayane Cristina dos Santos Prestes, Steffan Eduardo Silva Carneiro, Fernando Elias, Gabriel Eliseu, Thaise Emilio, Camila Laís Farrapo, Letícia Fernandes, Gustavo Ferreira, Joice Ferreira, Leandro Ferreira, Socorro Ferreira, Marcelo Fragomeni Simon, Maria Aparecida Freitas, Queila S. García, Angelo Gilberto Manzatto, Paulo Graça, Frederico Guilherme, Eduardo Hase, Niro Higuchi, Mariana Iguatemy, Reinaldo Imbrozio Barbosa, Margarita Jaramillo, Carlos Joly, Joice Klipel, Iêda Leão do Amaral, Carolina Levis, Antonio S. Lima, Maurício Lima Dan, Aline Lopes, Herison Madeiros, William E. Magnusson, Rubens Manoel dos Santos, Beatriz Marimon, Ben Hur Marimon Junior, Roberta Marotti Martelletti Grillo, Luiz Martinelli, Simone Matias Reis, Salomão Medeiros, Milton Meira-Junior, Thiago Metzker, Paulo Morandi, Natanael Moreira do Nascimento, Magna Moura, Sandra Cristina Müller, Laszlo Nagy, Henrique Nascimento, Marcelo Nascimento, Adriano Nogueira Lima, Raimunda Oliveira de Araújo, Jhonathan Oliveira Silva, Marcelo Pansonato, Gabriel Pavan Sabino, Karla Maria Pedra de Abreu, Pablo José Francisco Pena Rodrigues, Maria Piedade, Domingos Rodrigues, José Roberto Rodrigues Pinto, Carlos Quesada, Eliana Ramos, Rafael Ramos, Priscyla Rodrigues, Thaiane Rodrigues de Sousa, Rafael Salomão, Flávia Santana, Marcos Scaranello, Rodrigo Scarton Bergamin, Juliana Schietti, Jochen Schöngart, Gustavo Schwartz, Natalino Silva, Marcos Silveira, Cristiana Simão Seixas, Marta Simbine, Ana Claudia Souza, Priscila Souza, Rodolfo Souza, Tereza Sposito, Edson Stefani Junior, Julio Daniel do Vale, Ima Célia Guimarães Vieira, Dora Villela, Marcos Vital, Haron Xaud, Katia Zanini, Charles Eugene Zartman, Nur Khalish Hafizhah Ideris, Faizah binti Hj Metali, Kamariah Abu Salim, Muhd Shahruney Saparudin, Rafizah Mat Serudin, Rahayu Sukmaria Sukri, Serge Begne, George Chuyong, Marie Noel Djuikouo, Christelle Gonmadje, Murielle Simo-Droissart, Bonaventure Sonké, Hermann Taedoumg, Lise Zemagho, Sean Thomas, Fidèle Baya, Gustavo Saiz, Javier Silva Espejo, Dexiang Chen, Alan Hamilton, Yide Li, Tushou Luo, Shukui Niu, Han Xu, Zhang Zhou, Esteban Álvarez-Dávila, Juan Carlos Andrés Escobar, Henry Arellano-Peña, Jaime Cabezas Duarte, Jhon Calderón, Lina Maria Corrales Bravo, Borish Cuadrado, Hermes Cuadros, Alvaro Duque, Luisa Fernanda Duque, Sandra Milena Espinosa, Rebeca Franke-Ante, Hernando García, Alejandro Gómez, Roy González-M., Álvaro Idárraga-Piedrahíta, Eliana Jimenez, Rubén Jurado, Wilmar López Oviedo, René López-Camacho, Omar Aurelio Melo Cruz, Irina Mendoza Polo, Edwin Paky, Karen Pérez, Angel Pijachi, Camila Pizano, Adriana Prieto, Laura Ramos, Zorayda Restrepo Correa, James Richardson, Elkin Rodríguez, Gina M. Rodriguez M., Agustín Rudas, Pablo Stevenson, Markéta Chudomelová, Martin Dancak, Radim Hédl, Stanislav Lhota, Martin Svatek, Jacques Mukinzi, Corneille Ewango, Terese Hart, Emmanuel Kasongo Yakusu, Janvier Lisingo, Jean-Remy Makana, Faustin Mbayu, Benjamin Toirambe, John Tshibamba Mukendi, Lars Kvist, Gustav Nebel, Selene Báez, Carlos Céron, Daniel M. Griffith, Juan Ernesto Guevara Andino, David Neill, Walter Palacios, Maria Cristina Peñuela-Mora, Gonzalo Rivas-Torres, Gorky Villa, Sheleme Demissie, Tadesse Gole, Techane Gonfa, Kalle Ruokolainen, Michel Baisie, Fabrice Bénédet, Wemo Betian, Vincent Bezard, Damien Bonal, Jerôme Chave, Vincent Droissart, Sylvie Gourlet-Fleury, Annette Hladik, Nicolas Labrière, Pétrus Naisso, Maxime Réjou-Méchain, Plinio Sist, Lilian Blanc, Benoit Burban, Géraldine Derroire, Aurélie Dourdain, Clement Stahl, Natacha Nssi Bengone, Eric Chezeaux, Fidèle Evouna Ondo, Vincent Medjibe, Vianet Mihindou, Lee White, Heike Culmsee, Cristabel Durán Rangel, Viviana Horna, Florian Wittmann, Stephen Adu-Bredu, Kofi Affum-Baffoe, Ernest Foli, Michael Balinga, Anand Roopsind, James Singh, Raquel Thomas, Roderick Zagt, Indu K. Murthy, Kuswata Kartawinata, Edi Mirmanto, Hari Priyadi, Ismayadi Samsoedin, Terry Sunderland, Ishak Yassir, Francesco Rovero, Barbara Vinceti, Bruno Hérault, Shin-Ichiro Aiba, Kanehiro Kitayama, Armandu Daniels, Darlington Tuagben, John T. Woods, Muhammad Fitriadi, Alexander Karolus, Kho Lip Khoon, Noreen Majalap, Colin Maycock, Reuben Nilus, Sylvester Tan, Almeida Sitoe, Indiana Coronado G., Lucas Ojo, Rafael de Assis, Axel Dalberg Poulsen, Douglas Sheil, Karen Arévalo Pezo, Hans Buttgenbach Verde, Victor Chama Moscoso, Jimmy Cesar Cordova Oroche, Fernando Cornejo Valverde, Massiel Corrales Medina, Nallaret Davila Cardozo, Jano de Rutte Corzo, Jhon del Aguila Pasquel, Gerardo Flores Llampazo, Luis Freitas, Darcy Galiano Cabrera, Roosevelt García Villacorta, Karina Garcia Cabrera, Diego García Soria, Leticia Gatica Saboya, Julio Miguel Grandez Rios, Gabriel Hidalgo Pizango, Eurídice Honorio Coronado, Isau Huamantupa-Chuquimaco, Walter Huaraca Huasco, Yuri Tomas Huillca Aedo, Jose Luis Marcelo Peña, Abel Monteagudo Mendoza, Vanesa Moreano Rodriguez, Percy Núñez Vargas, Sonia Cesarina Palacios Ramos, Nadir Pallqui Camacho, Antonio Peña Cruz, Freddy Ramirez Arevalo, José Reyna Huaymacari, Carlos Reynel Rodriguez, Marcos Antonio Ríos Paredes, Lily Rodriguez Bayona, Rocio del Pilar Rojas Gonzales, Maria Elena Rojas Peña, Norma Salinas Revilla, Yahn Carlos Soto Shareva, Raul Tupayachi Trujillo, Luis Valenzuela Gamarra, Rodolfo Vasquez Martinez, Jim Vega Arenas, Christian Amani, Suspense Averti Ifo, Yannick Bocko, Patrick Boundja, Romeo Ekoungoulou, Mireille Hockemba, Donatien Nzala, Alusine Fofanah, David Taylor, Guillermo Bañares-de Dios, Luis Cayuela, Íñigo Granzow-de la Cerda, Manuel Macía, Juliana Stropp, Maureen Playfair, Verginia Wortel, Toby Gardner, Robert Muscarella, Hari Priyadi, Ervan Rutishauser, Kuo-Jung Chao, Pantaleo Munishi, Olaf Bánki, Frans Bongers, Rene Boot, Gabriella Fredriksson, Jan Reitsma, Hans ter Steege, Tinde van Andel, Peter van de Meer, Peter van der Hout, Mark van Nieuwstadt, Bert van Ulft, Elmar Veenendaal, Ronald Vernimmen, Pieter Zuidema, Joeri Zwerts, Perpetra Akite, Robert Bitariho, Colin Chapman, Eilu Gerald, Miguel Leal, Patrick Mucunguzi, Miguel Alexiades, Timothy R. Baker, Karina Banda, Lindsay Banin, Jos Barlow, Amy Bennett, Erika Berenguer, Nicholas Berry, Neil M. Bird, George A. Blackburn, Francis Brearley, Roel Brienen, David Burslem, Lidiany Carvalho, Percival Cho, Fernanda Coelho, Murray Collins, David Coomes, Aida Cuni-Sanchez, Greta Dargie, Kyle Dexter, Mat Disney, Freddie Draper, Muying Duan, Adriane Esquivel-Muelbert, Robert Ewers, Belen Fadrique, Sophie Fauset, Ted R. Feldpausch, Filipe França, David Galbraith, Martin Gilpin, Emanuel Gloor, John Grace, Keith Hamer, David Harris, Tommaso Jucker, Michelle Kalamandeen, Bente Klitgaard, Aurora Levesley, Simon L. Lewis, Jeremy Lindsell, Gabriela Lopez-Gonzalez, Jon Lovett, Yadvinder Malhi, Toby Marthews, Emma McIntosh, Karina Melgaço, William Milliken, Edward Mitchard, Peter Moonlight, Sam Moore, Alexandra Morel, Julie Peacock, Kelvin Peh, Colin Pendry, R. Toby Pennington, Luciana de Oliveira Pereira, Carlos Peres, Oliver L. Phillips, Georgia Pickavance, Thomas Pugh, Lan Qie, Terhi Riutta, Katherine Roucoux, Casey Ryan, Tiina Sarkinen, Camila Silva Valeria, Dominick Spracklen, Suzanne Stas, Martin Sullivan, Michael Swaine, Joey Talbot, James Taplin, Geertje van der Heijden, Laura Vedovato, Simon Willcock, Mathew Williams, Luciana Alves, Patricia Alvarez Loayza, Gabriel Arellano, Cheryl Asa, Peter Ashton, Gregory Asner, Terry Brncic, Foster Brown, Robyn Burnham, Connie Clark, James Comiskey, Gabriel Damasco, Stuart Davies, Tony Di Fiore, Terry Erwin, William Farfan-Rios, Jefferson Hall, David Kenfack, Thomas Lovejoy, Roberta Martin, Olga Martha Montiel, John Pipoly, Nigel Pitman, John Poulsen, Richard Primack, Miles Silman, Marc Steininger, Varun Swamy, John Terborgh, Duncan Thomas, Peter Umunay, Maria Uriarte, Emilio Vilanova Torre, Ophelia Wang, Kenneth Young, Gerardo A. Aymard C., Lionel Hernández, Rafael Herrera Fernández, Hirma Ramírez-Angulo, Pedro Salcedo, Elio Sanoja, Julio Serrano, Armando Torres-Lezama, Tinh Cong Le, Trai Trong Le, Hieu Dang Tra

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Design of Noble Metal Nanostructures for Heterogeneous Catalytic Applications

Worldwide efforts have been focused to introduce greener chemical and energetic processes that drive the society away from the dependency on fossil fuels, looking to reduce the environmental footprint of modern societies. Catalysis for instance, has been for decades the winning technology which helps to improve the efficiency of processes in petrochemical, pharmaceutical, and biomedical industries to mention a few. Efficiency of catalysts come mostly from its structure and composition which proportionate high activity and selectivity. However, the use of expensive noble metals as catalyst materials remains a key issue for industrial applications. Thus, developing materials that reduce and mitigate carbon dioxide emissions as well as decrease of waste of the materials using during these processes remain a tremendous challenge to overcome. Nanotechnology for instance, is a growing technology with great impact in the industrial,pharmaceutical and energetical sectors. In fact, nanomaterials provide a better economical option, less waste and still with superior performance than their bulk counterparts which is explained from their reduce size, shape and larger surface areas which leads to overall higher catalytic performance. Nanocatalysis modify the rate of a chemical reaction by speeding up or accelerating the reaction rate without being consumed, making the process more energetically favored. Nanocatalyst have significant impact in different industrial processes as chemical reactions to produce fine chemicals, or for renewable energy and among others. As it was mentioned previously, the high performance of nanocatalyst is associated with the atoms at the surface of the nanostructure which are known as the active sites for catalysis. Moreover, it is well known that surface atoms placed at the corner or edges of the nanocatalyst are more active than those surface atoms at planes, and it the same manner with surface-to-volume ratio, their number will increase with decrease of particle size. In addition to nanoparticle size, crystallographic facets lead to different shapes or morphologies which are also contributing to the number of atoms at the surface, edges and corners. All of these contributing together to the efficiently performance of nanocatalyst for the target reactions . In this thesis is presented nanocatalyst materials development, and studies about their synergetic effect of the different components for heterogeneous catalytic applications.First, benzaldehyde byproduct is an intermediate in the production of fine chemicals and additives. Tuning selectivity to benzaldehyde is therefore critical in alcohol oxidation reactions at the industrial level where the typical methods employ toxic oxidant chemicals for its production. Herein, we report a simple but innovative method for the synthesis of palladium hydride and nickel palladium hydride nanodendrites with controllable morphology, high stability, and excellent catalytic activity. The synthesized dendrites can maintain the palladium hydride phase even after their use in the chosen catalytic reaction. Remarkably, the high surface area morphology and unique interaction between nickel-rich surface and palladium hydride (β-phase) of these nanodendrites are translated in an enhanced catalytic activity for benzyl alcohol oxidation reaction. Our Ni/PdH0.43 nanodendrites demonstrated a high selectivity towards benzaldehyde of about 92.0% with a conversion rate of 95.4%, showing higher catalytic selectivity than their PdH0.43 counterparts and commercial Pd/C. The present study opens the door for further exploration of metal/metal-hydride nanostructures as next-generation catalytic materials.Second, palladium hydride system (PdHx) has been of great interest primarily due to the high solubility of hydrogen on the palladium fcc (Pd-face centered cubic) lattice which make them suitable candidates as environmental friendly materials for applications in terms of storage and use of energy, having specific relevance in hydrogen storage, fuel cell, batteries, kinetics reversibility studies, and more. Palladium hydride properties do not only include adsorption and desorption of hydrogen, but they are also effective for electrocatalytic applications. Overall, palladium hydride and its alloys properties are strongly correlated with their electronic and crystal structure changes. Thus, a deep understanding and methodology for their production is crucial for their use in the mentioned applications. Despite of the studies found in literature, there is still a lack of studies for direct but simple synthesis of palladium hydride with practical applications. For instance, palladium hydride literature studies are mostly based on in-situ studies where a limitation of sample, stability and reproducibility are some of the major problems associated with them which also leads to a lack of studies related to their properties and how to tune them. Herein, we reported a simple yet well designed method for the synthesis of stable β palladium hydride with different morphologies and decoration of its surface with organic ligands which lead to different effects in terms of nanocrystal sizes and the ability of tune of its properties. Upon the use of different capping agents during the synthesis, diverse magnetic properties have arisen, as well as an increase in their hydrogen storage capacity. These properties are found to be different from their counterpart of pure palladium and palladium hydride material without coating agents.Third, developing non-platinum materials with enhance performance for electrocatalytic reactions has been gaining attention in recently years. Palladium and Palladium-based materials are the most suitable candidates to substitute platinum catalysts in anodic and cathodic reactions. Here we developed a facile path to synthesize PdCu nanowires having alloy and intermetallic phases within their structures. To the best of our knowledge, the catalytic properties of *PdCu intermetallic nanowires for hydrogen evolution reaction and formic acid oxidation reaction are higher than their PdCu alloy counterpart and those previously reported for 0D and 1D bimetallic nanostructures. Tafel slopes and overpotential presented here during hydrogen evolution reaction of *PdCu NWs in both acidic and basic conditions are superior than PdCu alloy nanowires, Pd nanowires and comparable to commercial Pt. In terms of formic acid oxidation reaction, *PdCu NWs also exhibits the highest mass activity, followed by PdCu alloy NWs, and being both superior than commercial Pd. In addition, PdCu nanowires also exhibit superior stability for both reactions: hydrogen evolution reaction in acid and basic conditions, and formic acid oxidation reaction as well as good resistance against CO poisoning. Density functional theory (DFT) calculations demonstrate that the improved HER performance at acidic condition is due to the decrease in the hydrogen binding energy of the compressed PdCu-B2 phase, and the improved HER performance at alkaline condition is due to the reduced water dissociation barriers at alkaline condition of *PdCu intermetallic phase

Design of Noble Metal Nanostructures for Heterogeneous Catalytic Applications

Worldwide efforts have been focused to introduce greener chemical and energetic processes that drive the society away from the dependency on fossil fuels, looking to reduce the environmental footprint of modern societies. Catalysis for instance, has been for decades the winning technology which helps to improve the efficiency of processes in petrochemical, pharmaceutical, and biomedical industries to mention a few. Efficiency of catalysts come mostly from its structure and composition which proportionate high activity and selectivity. However, the use of expensive noble metals as catalyst materials remains a key issue for industrial applications. Thus, developing materials that reduce and mitigate carbon dioxide emissions as well as decrease of waste of the materials using during these processes remain a tremendous challenge to overcome. Nanotechnology for instance, is a growing technology with great impact in the industrial,pharmaceutical and energetical sectors. In fact, nanomaterials provide a better economical option, less waste and still with superior performance than their bulk counterparts which is explained from their reduce size, shape and larger surface areas which leads to overall higher catalytic performance. Nanocatalysis modify the rate of a chemical reaction by speeding up or accelerating the reaction rate without being consumed, making the process more energetically favored. Nanocatalyst have significant impact in different industrial processes as chemical reactions to produce fine chemicals, or for renewable energy and among others. As it was mentioned previously, the high performance of nanocatalyst is associated with the atoms at the surface of the nanostructure which are known as the active sites for catalysis. Moreover, it is well known that surface atoms placed at the corner or edges of the nanocatalyst are more active than those surface atoms at planes, and it the same manner with surface-to-volume ratio, their number will increase with decrease of particle size. In addition to nanoparticle size, crystallographic facets lead to different shapes or morphologies which are also contributing to the number of atoms at the surface, edges and corners. All of these contributing together to the efficiently performance of nanocatalyst for the target reactions . In this thesis is presented nanocatalyst materials development, and studies about their synergetic effect of the different components for heterogeneous catalytic applications.First, benzaldehyde byproduct is an intermediate in the production of fine chemicals and additives. Tuning selectivity to benzaldehyde is therefore critical in alcohol oxidation reactions at the industrial level where the typical methods employ toxic oxidant chemicals for its production. Herein, we report a simple but innovative method for the synthesis of palladium hydride and nickel palladium hydride nanodendrites with controllable morphology, high stability, and excellent catalytic activity. The synthesized dendrites can maintain the palladium hydride phase even after their use in the chosen catalytic reaction. Remarkably, the high surface area morphology and unique interaction between nickel-rich surface and palladium hydride (β-phase) of these nanodendrites are translated in an enhanced catalytic activity for benzyl alcohol oxidation reaction. Our Ni/PdH0.43 nanodendrites demonstrated a high selectivity towards benzaldehyde of about 92.0% with a conversion rate of 95.4%, showing higher catalytic selectivity than their PdH0.43 counterparts and commercial Pd/C. The present study opens the door for further exploration of metal/metal-hydride nanostructures as next-generation catalytic materials.Second, palladium hydride system (PdHx) has been of great interest primarily due to the high solubility of hydrogen on the palladium fcc (Pd-face centered cubic) lattice which make them suitable candidates as environmental friendly materials for applications in terms of storage and use of energy, having specific relevance in hydrogen storage, fuel cell, batteries, kinetics reversibility studies, and more. Palladium hydride properties do not only include adsorption and desorption of hydrogen, but they are also effective for electrocatalytic applications. Overall, palladium hydride and its alloys properties are strongly correlated with their electronic and crystal structure changes. Thus, a deep understanding and methodology for their production is crucial for their use in the mentioned applications. Despite of the studies found in literature, there is still a lack of studies for direct but simple synthesis of palladium hydride with practical applications. For instance, palladium hydride literature studies are mostly based on in-situ studies where a limitation of sample, stability and reproducibility are some of the major problems associated with them which also leads to a lack of studies related to their properties and how to tune them. Herein, we reported a simple yet well designed method for the synthesis of stable β palladium hydride with different morphologies and decoration of its surface with organic ligands which lead to different effects in terms of nanocrystal sizes and the ability of tune of its properties. Upon the use of different capping agents during the synthesis, diverse magnetic properties have arisen, as well as an increase in their hydrogen storage capacity. These properties are found to be different from their counterpart of pure palladium and palladium hydride material without coating agents.Third, developing non-platinum materials with enhance performance for electrocatalytic reactions has been gaining attention in recently years. Palladium and Palladium-based materials are the most suitable candidates to substitute platinum catalysts in anodic and cathodic reactions. Here we developed a facile path to synthesize PdCu nanowires having alloy and intermetallic phases within their structures. To the best of our knowledge, the catalytic properties of *PdCu intermetallic nanowires for hydrogen evolution reaction and formic acid oxidation reaction are higher than their PdCu alloy counterpart and those previously reported for 0D and 1D bimetallic nanostructures. Tafel slopes and overpotential presented here during hydrogen evolution reaction of *PdCu NWs in both acidic and basic conditions are superior than PdCu alloy nanowires, Pd nanowires and comparable to commercial Pt. In terms of formic acid oxidation reaction, *PdCu NWs also exhibits the highest mass activity, followed by PdCu alloy NWs, and being both superior than commercial Pd. In addition, PdCu nanowires also exhibit superior stability for both reactions: hydrogen evolution reaction in acid and basic conditions, and formic acid oxidation reaction as well as good resistance against CO poisoning. Density functional theory (DFT) calculations demonstrate that the improved HER performance at acidic condition is due to the decrease in the hydrogen binding energy of the compressed PdCu-B2 phase, and the improved HER performance at alkaline condition is due to the reduced water dissociation barriers at alkaline condition of *PdCu intermetallic phase