Surface-modified carbon materials for CO2 electroreduction

The electrochemical reduction of CO2 to produce sustainable fuels and chemicals has attracted great attention in recent years. It is shown that surface-modified carbons catalyze the CO2RR. This study reports a strategy to modify the surface of commercially available carbon materials by adding oxygen and nitrogen surface groups without modifying its graphitic structure. Clear differences in CO2RR activity, selectivity and the turnover frequency between the surface-modified carbons were observed, and these differences were ascribed to the nature of the surface groups chemistry and the point of zero charge (PZC). The results show that nitrogen-containing surface groups are highly selective towards the formation of CO from the electroreduction of CO2 in comparison with the oxygen-containing surface groups, and the carbon without surface groups. This demonstrates that the selectivity of carbon for CO2RR can be rationally tuned by simply altering the surface chemistry via surface functionalization

Surface-Modified Carbon Materials for CO2 Electroreduction

The electrochemical reduction of CO2 to produce sustainable fuels and chemicals has attracted great attention in recent years. It is shown that surface-modified carbons catalyze the CO2RR. This study reports a strategy to modify the surface of commercially available carbon materials by adding oxygen and nitrogen surface groups without modifying its graphitic structure. Clear differences in CO2RR activity, selectivity and the turnover frequency between the surface-modified carbons were observed, and these differences were ascribed to the nature of the surface groups chemistry and the point of zero charge (PZC). The results show that nitrogen-containing surface groups are highly selective towards the formation of CO from the electroreduction of CO2 in comparison with the oxygen-containing surface groups, and the carbon without surface groups. This demonstrates that the selectivity of carbon for CO2RR can be rationally tuned by simply altering the surface chemistry via surface functionalization

Copper sulfide derived nanoparticles supported on carbon for the electrochemical reduction of carbon dioxide

The electrocatalytic reduction of CO2 to produce sustainable fuels and chemicals is attracting great attention. Cu-based catalysts can lead to the production of a range of different molecules, and interestingly the product selectivity strongly depends on the preparation history, although it is not fully understood yet why. We report a novel strategy that allowed us to prepare Cu nanoparticle on carbon catalysts with similar morphologies, but prepared by in-situ reduction of either supported CuS, Cu2S or CuO nanoparticles. For the first time the evolution of the Cu species was followed under CO2 and H+ reduction conditions using in-situ X-ray absorption spectroscopy. Excellent electrochemical contact between the Cu-based nanoparticles, the carbon support and the carbon-paper substrate was observed, resulting in metallic Cu as the predominant phase under typical electrochemical CO2 reduction conditions. Even covering less than 4% of the H2 producing carbon support with Cu-sulfide derived nanoparticles allowed to steer the selectivity to a maximum of 12% Faradaic efficiency for the production of formate. Clear differences between the catalysts derived from CuS, Cu2S or CuO nanoparticles were observed, which was ascribed to the presence of residual sulfur in the catalysts

Functional Effects of Prebiotic Fructans in Colon Cancer and Calcium Metabolism in Animal Models

Inulin-type fructans are polymers of fructose molecules and are known for their capacity to enhance absorption of calcium and magnesium, to modulate gut microbiota and energy metabolism, and to improve glycemia. We evaluated and compared the effects of Chicory inulin “Synergy 1®” and inulin from Mexican agave “Metlin®” in two experimental models of colon cancer and bone calcium metabolism in mice and rats. Inulins inhibited the development of dextran sulfate sodium-induced colitis and colon cancer in mice; these fructans reduced the concentration of tumor necrosis factor alpha and prevented the formation of intestinal polyps, villous atrophy, and lymphoid hyperplasia. On the other hand, inulin treatments significantly increased bone densitometry (femur and vertebra) in ovariectomized rats without altering the concentration of many serum biochemical parameters and urinary parameters. Histopathology results were compared between different experimental groups. There were no apparent histological changes in rats treated with inulins and a mixture of inulins-isoflavones. Our results showed that inulin-type fructans have health-promoting properties related to enhanced calcium absorption, potential anticancer properties, and anti-inflammatory effects. The use of inulin as a prebiotic can improve health and prevent development of chronic diseases such as cancer and osteoporosis

Copper sulfide derived nanoparticles supported on carbon for the electrochemical reduction of carbon dioxide

The electrocatalytic reduction of CO2 to produce sustainable fuels and chemicals is attracting great attention. Cu-based catalysts can lead to the production of a range of different molecules, and interestingly the product selectivity strongly depends on the preparation history, although it is not fully understood yet why. We report a novel strategy that allowed us to prepare Cu nanoparticle on carbon catalysts with similar morphologies, but prepared by in-situ reduction of either supported CuS, Cu2S or CuO nanoparticles. For the first time the evolution of the Cu species was followed under CO2 and H+ reduction conditions using in-situ X-ray absorption spectroscopy. Excellent electrochemical contact between the Cu-based nanoparticles, the carbon support and the carbon-paper substrate was observed, resulting in metallic Cu as the predominant phase under typical electrochemical CO2 reduction conditions. Even covering less than 4% of the H2 producing carbon support with Cu-sulfide derived nanoparticles allowed to steer the selectivity to a maximum of 12% Faradaic efficiency for the production of formate. Clear differences between the catalysts derived from CuS, Cu2S or CuO nanoparticles were observed, which was ascribed to the presence of residual sulfur in the catalysts.ChemE/Materials for Energy Conversion & Storag

Copper sulfide derived nanoparticles supported on carbon for the electrochemical reduction of carbon dioxide

The electrocatalytic reduction of CO2 to produce sustainable fuels and chemicals is attracting great attention. Cu-based catalysts can lead to the production of a range of different molecules, and interestingly the product selectivity strongly depends on the preparation history, although it is not fully understood yet why. We report a novel strategy that allowed us to prepare Cu nanoparticle on carbon catalysts with similar morphologies, but prepared by in-situ reduction of either supported CuS, Cu2S or CuO nanoparticles. For the first time the evolution of the Cu species was followed under CO2 and H+ reduction conditions using in-situ X-ray absorption spectroscopy. Excellent electrochemical contact between the Cu-based nanoparticles, the carbon support and the carbon-paper substrate was observed, resulting in metallic Cu as the predominant phase under typical electrochemical CO2 reduction conditions. Even covering less than 4% of the H2 producing carbon support with Cu-sulfide derived nanoparticles allowed to steer the selectivity to a maximum of 12% Faradaic efficiency for the production of formate. Clear differences between the catalysts derived from CuS, Cu2S or CuO nanoparticles were observed, which was ascribed to the presence of residual sulfur in the catalysts

Territorialidades, migración y políticas públicas en el contexto rural latinoamericano

Teniendo como antecedente el interés de investigadores e investigadoras de la Universidad Autónoma del Estado de México (uaem) en los temas de desarrollo, género y participación social, el Cuerpo Académico Procesos Sociales en el Medio Rural del Instituto de Ciencias Agropecuarias y Rurales genera la propuesta de establecer una cooperación académica para el desarrollo científico, social y ambiental de los territorios. Así, se consolida la Red Internacional de Procesos Participativos, Género y Desarrollo Territorial, que de manera interdisciplinaria aborda temas transversales relacionados con los procesos participativos de hombres y mujeres en los diversos espacios productivos, públicos, institucionales y regionales, además de su impacto en temas en el desarrollo de sectores o territorios específicos, especialmente de zonas rurales donde la marginación y la pobreza persisten como factores limitantes para la prosperidad nacional. A esta propuesta de Red se adhieren de manera importante los siguientes Cuerpos Académicos de la uaem: 1) Estudios Agroalimentarios, 2) Desarrollo Social y Político en México y América Latina, 3) Género, Migraciones y Desigualdades, y 4) Sustentabilidad, Territorio y Educación. Además de Grupos de Investigación de Colombia, Ecuador y Chile como Grupo Gestión y Desarrollo Rural de la Universidad Nacional de Colombia (gigdr), Grupo de Investigación del Instituto de Investigaciones del Ecuador, y Grupo de investigación en Migraciones, Representaciones de Género, Lengua, Te- rritorialidad y Exclusión Social de la Universidad Católica del Maule-Chile. Cabe destacar que todos ellos poseen amplia experiencia y reconocimiento en los temas de desarrollo territorial y local. Bajo estas circunstancias surge la idea de publicar un libro, en el que se considera que el territorio es un constructo social complejo y abierto, de dinámica colectiva, donde los actores como la academia, las instituciones y las comunidades locales interactúan en una red de conocimiento y de saberes que permite a los procesos participativos una identidad más precisa, con referentes definidos de encuentro y de interacción, especialmente en zonas rurales de Latinoamérica.Instituto de Ciencias Agropecuarias y Rurales, Centro de Investigación en Ciencias Sociales y Humanidades, Red Internacional de Procesos Participativos,Género y Desarrollo Territoria