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Electrofluorochromism (EFC) is a phenomenon widely employed for the development of optoelectronic devices. In this work, we applied EFC as a powerful tool in sensing applications. The ability to tune the photoluminescence emission by controlling the applied potential may help maximize the response to target molecules. We have explored the EFC of the conjugated copolymer poly[9,9-dioctylfluorene-alt-benzothiadiazole] (F8BT) to design an electrofluorochromic sensor able to detect emerging pollutants with a significant impact in the marine ecosystems. In particular, a sulfonic acid-based chemical sunscreen (Ecamsule) was used as a model molecule. The photoluminescence emission modulation is affected by the presence of Ecamsule, which is attributed to the enhanced quenching process of F8BT during the p-doping process. The quenching is due to the formation of exciplex-like within the conjugated film upon the insertion of the organic anionic molecule in the polymer chain. The developed F8BT-based electrofluorochromic sensor displays a low limit of detection and good selectivity in the presence of interfering anions that are common in seawater.

The present contribution describes an electrochemical system for the detection of alkaline phosphatase (ALP) enzyme inhibitors in seawater medium. Fluorescence spectroscopy and thermal unfolding results suggest that the state of free ALP is affected in this medium, yet the protein remains active. The enzyme activity can be evaluated using hydroquinone diphosphate as the substrate, with hydroquinone as the electrochemically monitored product. It has been demonstrated that encapsulation in conventional and organic modified silica matrices maintains ALP integrity, although diffusion across the formed monoliths hinders the electrochemical response. ALP@Phenyl-modified silica exhibits the best performance due to higher affinity between substrate molecules and aromatic moieties and, probably, to larger pore size. This electrochemical system can detect and quantify calyculin A in seawater at sub-nanomolar concentrations and it can also be employed for the development of electrochemical biosensors tailored for the marine environment.

Pt nanoparticles were incorporated on carbon black (Vulcan XC-72R) and an activated carbon (F400) using a fast and efficient microwave method. For the preparation, a Pt solution was contacted with the corresponding carbon sample and heated up to 110°C in a microwave oven using an optimised heating rate. TEM images revealed that the carbon-supported Pt nanoparticles had a small average particle size and high dispersion. These Pt-based electrocatalysts showed both high electrocatalytic activity and selectivity towards the 4-electron pathway for the oxygen reduction reaction (ORR) in acid and alkaline media. In addition, they presented excellent stability and resistance to CO poisoning. Moreover, the as-prepared electrocatalysts exhibited outstanding electrocatalytic behaviour for the hydrogen evolution reaction (HER). It should be highlighted that, even though our Pt-based electrocatalysts have much lower loadings than that of the commercial Pt/C sample (used as reference), the electroactive surface areas of as-prepared electrocatalysts were higher compared to the reference electrocatalyst. Such small and well-dispersed Pt NPs with an enhanced electroactive surface area and strong interaction with the carbon support, led to an improvement of the current density normalised by Pt loading (A gPt−1).

La experiencia docente descrita en este trabajo trata sobre el aprendizaje asíncrono sobre medio ambiente y energías sostenibles mediante el uso de una herramienta en línea. Para llevar a cabo dicha experiencia, se preparó un curso mediante la plataforma Moodle, el cual estaba dividido en 4 bloques temáticos ((I) El Cambio Climático: Una Realidad Cotidiana; (II) Energías Sostenibles; (III) Almacenamiento de Energía Sostenible; (IV) El Camino hacia la Sostenibilidad), cada uno de los cuales estaba formado por una serie de diapositivas con el contenido teórico, acompañado de una introducción audiovisual y material complementario que permitía al alumnado profundizar en los temas abordados. Además, al final del curso el alumnado debía contestar a un cuestionario sobre el contenido teórico del mismo y a una encuesta que recababa su opinión sobre el empleo de entornos de aprendizaje virtual asíncrono. Los resultados obtenidos pusieron de manifiesto el interés del alumnado por el empleo de dichos entornos de aprendizaje y el gran potencial de los mismos, los cuales están en línea con los intereses de las nuevas generaciones.

Formic acid has been postulated as one of the most promising liquid organic hydrogen carriers. Numerous studies dealing with the development of efficient catalysts able to boost the dehydrogenation of formic acid can be found in recent literature. However, most of them lack in stability, so that finding stable catalysts is highly desirable yet challenging. In the present study, we developed Pd-based biomass-derived carbon-supported catalysts by following a simple protocol. The effect of the modification of both the metal phase and support has been assessed by incorporating Ag in the form of bimetallic nanoparticles and nitrogen functional groups, respectively. The effect of the method followed for the preparation of the catalysts was also checked. It has been found that the resulting PdAg-based catalysts supported on N-doped biomass-derived carbon materials showed suitable activity and excellent stability under reaction conditions. The present study highlights the potential of modulating the features of the catalysts, not only in terms of the composition of the metal phase and incorporation of heteroatoms in the support, but also in terms of the synthetic protocol used.

In this study, we synthesized MnFe2O4 solid nanospheres (MSN) calcined at different temperatures (200–500 °C) and MSN-based materials mixed with carbon black, for their use as electrocatalysts in the oxygen reduction reaction (ORR) in alkaline medium (0.1 M KOH). It was demonstrated that the calcination temperature of MSN material determined its chemical surface composition and microstructure and it had an important effect on the electrocatalytic properties for ORR, which in turn was reflected in the performance of MSN/CB-based electrocatalysts. The study revealed that the presence of Mn species plays a key role in the ORR activity. Among tested, MSN200/CB and MSN350/CB exhibited the best electrochemical performances together with outstanding stability.

Firstly, Polyaniline-derived@poly(styrene sulfonate) (PANI-derived@PSS) hydrogel materials have been prepared by supramolecular self-assembly between positively charged poly(aniline-co-piperazine) (poly(Ani-co-Pip) chain and negatively-charged PSS chain by oxidative polymerization method. The study of the monomer ratio (X) (aniline:piperazine) has been analyzed. Afterwards, symmetric capacitors based on poly(ANI-co-Pip)@PSS-X mixed with Vulcan (Vu) have been studied. A combination of different techniques like cyclic voltammetry, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and Thermogravimetric analyses (TGA) were applied to characterize both the chemical structure and the behavior of the hydrogels. The different hydrogels have exhibited electrical conductivity and electroactivity in acid conditions. Moreover, the effects of Vulcan on the structure and properties of poly(ANI-co-Pip)@PSS have been investigated. Additionally, supercapacitors based on as-prepared poly(ANI-co-Pip)/Vu@PSS displayed an improvement of capacitor performance compare to that of conventional hydrogels-based capacitors. This study offers valuable hints for achieving the preparation of supramolecular materials.

La experiencia docente desarrollada en este trabajo se basa en la utilización de entornos de aprendizaje virtual en asignaturas del área de Química Inorgánica. Dichos entornos de aprendizaje virtual son una herramienta muy útil para afianzar los conceptos y conocimiento adquiridos durante las clases teóricas y experimentales. El empleo de dichos entornos de aprendizaje ha servido para fomentar el interés de las nuevas generaciones de personas científicas haciendo uso de las Tecnologías del Aprendizaje y el Conocimiento (TAC). En la presente experiencia docente se ha empleado la plataforma desarrollada por la empresa Labster, la cual ofrece un amplio catálogo con experiencias de laboratorio virtual relacionadas con temas generales abordados en los laboratorios de química. En esta experiencia docente se ha empleado dicho entorno de aprendizaje en forma de laboratorio virtual a modo de complemento de las clases prácticas que se imparten en la asignatura de Experimentación en Química Inorgánica, del tercer curso del Grado de Química de la Universidad de Alicante. La experiencia docente se evaluó mediante una encuesta preparada con Google Forms y los resultados han puesto de manifiesto que el alumnado muestra gran motivación por el empleo de entornos de aprendizaje online.

Life Cycle Assessment (LCA) is applied to eco-design the H3PO4-assisted hydrothermal carbonization (HTC) process converting biomass residue into high-value products. The main innovation of the process relies on the combination of the H3PO4-assisted HTC with the activation treatment of the obtained hydrochar, resulting in activated carbon that is then functionalized. In addition, the liquid phase obtained from HTC is eventually purified to extract levulinic acid. Under average conditions at the laboratory scale (reference), the LCA showed that electricity consumption is the main contributor (45–70%) to impacts on climate change, photochemical ozone formation, acidification, freshwater eutrophication, freshwater ecotoxicity and fossil resources use. Pyridine, the main chemical used in the functionalization stage, contributes to impacts on human toxicity and on marine eutrophication respectively by 77.3% and 47.3%. Building on these results, two further scenarios were studied, one considering the maximum capacity of each equipment and another one assuming the potential improvements once the process will be upscaled. The scenarios were validated in a series of laboratory scale tests. Depending on the environmental impact category chosen, the results showed a reduction potential of 30–65% as compared to the reference scenario. These findings confirm the added value of LCA in the ecodesign of technologies and pave the way to further improvements of the technology itself but also of the LCA methodology used for the assessment.