Design of Activated Carbon/Activated Carbon Asymmetric Capacitors

Supercapacitors are energy storage devices that offer a high power density and a low energy density in comparison with batteries. Their limited energy density can be overcome by using asymmetric configuration in mass electrodes, where each electrode works within their maximum available potential window, rendering the maximum voltage output of the system. Such asymmetric capacitors are optimized using the capacitance and the potential stability limits of the electrodes, with the reliability of the design largely depending on the accuracy and the approach taken for the electrochemical characterization. Therefore, the performance could be lower than expected and even the system could break down, if a well thought out procedure is not followed. In this work, a procedure for the development of asymmetric supercapacitors based on activated carbons is detailed. Three activated carbon materials with different textural properties and surface chemistry have been systematically characterized in neutral aqueous electrolyte. The asymmetric configuration of the masses of both electrodes in the supercapacitor has allowed to cover a higher potential window, resulting in an increase of the energy density of the three devices studied when compared with the symmetric systems, and an improved cycle life.

Molecular Techniques (2015-2016). Lesson 7

Powerpoint slides for Lesson 7.

Molecular Techniques (2015-2016). Lesson 8

Powerpoint slides for Lesson 8.

Molecular Techniques (2015-2016). Lesson 9

Powerpoint slides for Lesson 9.

Molecular Techniques (2015-2016). Lesson 10

Powerpoint slides for Lesson 10.

Molecular Techniques (2015-2016). Protocol for the Genetics Laboratory practices

Protocol for the Genetics Laboratory practices.

Molecular Techniques (2015-2016). Slides for the Genetics Laboratory practices introduction

Slides for the Genetics Laboratory practices introduction.

Molecular Techniques (2015-2016). Exercises to be discussed and solved during the laboratory practices

Exercises to be discussed and solved during the laboratory practices.

Molecular Techniques (2015-2016). Problems to be solved by the students

Problems to be solved by the students.

New hybrid materials based on the grafting of Pd(II)-amino complexes on the graphitic surface of AC: preparation, structures and catalytic properties

A novel procedure for the preparation of solid Pd(II)-based catalysts consisting of the anchorage of designed Pd(II)-complexes on an activated carbon (AC) surface is reported. Two molecules of the Ar–S–F type (where Ar is a plane-pyrimidine moiety, F a Pd(II)-ligand and S an aliphatic linker) differing in F, were grafted on AC by π–π stacking of the Ar moiety and the graphene planes of the AC, thus favouring the retaining of the metal-complexing ability of F. Adsorption of Pd(II) by the AC/Ar–S–F hybrids occurs via Pd(II)-complexation by F. After deep characterization, the catalytic activities of the AC/Ar–S–F/Pd(II) hybrids on the hydrogenation of 1-octene in methanol as a catalytic test were evaluated. 100% conversion to n-octane at T = 323.1 K and P = 15 bar, was obtained with both catalysts and most of Pd(II) was reduced to Pd(0) nanoparticles, which remained on the AC surface. Reusing the catalysts in three additional cycles reveals that the catalyst bearing the F ligand with a larger Pd-complexing ability showed no loss of activity (100% conversion to n-octane) which is assigned to its larger structural stability. The catalyst with the weaker F ligand underwent a progressive loss of activity (from 100% to 79% in four cycles), due to the constant aggregation of the Pd(0) nanoparticles. Milder conditions, T = 303.1 K and P = 1.5 bar, prevent the aggregation of the Pd(0) nanoparticles in this catalyst allowing the retention of the high catalytic efficiency (100% conversion) in four reaction cycles.

TRANSVERSA: coordinación de actividades transversales del módulo básico de los grados en Biología y Ciencias del Mar

Esta red de investigación en docencia universitaria ha centrado sus objetivos en la coordinación de las actividades transversales en el módulo básico de los Grados en Biología y en Ciencias del Mar. Además, entre los intereses principales de la red se ha fijado la evaluación y propuestas de mejora de la planificación de las actividades con carga no presencial. En las sucesivas reuniones se ha contado con la participación de los delegados y delegadas de los distintos grupos y sus contribuciones han permitido incorporar la opinión del alumnado. Así, se ha establecido un primer análisis de la problemática a abordar en los siguientes años para mejorar la coordinación transversal y vertical en ambos grados, así como también se ha buscado una solución a todos los inconvenientes que han surgido a lo largo del semestre. Se plantea a su vez la mejora en la distribución de la carga semanal para evitar que haya semanas con mucha carga de horas no presenciales. Finalmente, se ha coordinado las competencias transversales en las asignaturas que comparten estos objetivos.