Main factors influencing ecosystem restoration outcomes: a global qualitative meta-analysis

43 p.Ecosystem restoration (ER) has been proven useful to help reversing ecosystem degradation caused by human activities and its consequent loss of biodiversity. However, its current efficiency is limited, and it is not meeting the initial expectations. In order to know what is defining this limited performance, the main goal of this study is to know the main elements hampering and improving the outcomes of ER. For this purpose, we performed a global qualitative meta-analysis of 131 reviews on ER in all types of ecosystems. From the reviews, we extracted 579 qualitative variables subsequently categorized into 25 factors to which a weight value was assigned. These factors cover different aspects like policy, economy, society, practice and science. We concluded that the choice of restoration techniques, the performance assessment and evaluation, and the temporal scale of the restoration project were the factors with highest influence on ER results. We also highlighted the need of deeper scientific research on more complex ecological attributes as a crucial element to tackle several factors. With these results, we provide guidelines to improve the performance of current ER from a local (practice) to a global (international strategies) scales.La restauración de ecosistemas (RE) se ha probado útil para ayudar a revertir la degradación de ecosistemas causada por la actividad humana y su consecuente pérdida de biodiversidad. Sin embargo, su actual eficiencia es limitada y no está cumpliendo con las expectativas iniciales. Para saber qué define estas limitaciones, el principal objetivo de este estudio es conocer los principales elementos que están obstaculizando y mejorando los resultados de la RE. Con este propósito, llevamos a cabo un meta-análisis cualitativo global de 131 revisiones sobre la RE en todo tipo de ecosistemas. De las revisiones, extrajimos 579 variables cualitativas posteriormente categorizadas en 25 factores a los cuales se les asignó un peso. Estos factores cubren diferentes aspectos de la RE como la política, la economía, la sociedad, la práctica y la ciencia. Concluimos que la elección de las técnicas de restauración, la evaluación de la actuación y la escala temporal del proyecto de restauración fueron los factores con la mayor influencia en los resultados de la RE. También reseñamos la necesidad de profundizar en el estudio de atributos ecológicos más complejos como elemento crucial para abordar diferentes factores. Con estos resultados, proveemos una guía para mejorar la actuación de la RE desde la escala local (práctica) hasta la global (estrategias internacionales).Máster Universitario en Restauración de Ecosistema

Stability and electrochemical performance of nanostructured La2CuO4þd cathodes

La2CuO4þd cathode layers are prepared by spray-pyrolysis deposition and their structural, microstructural and electrical properties are compared with those of submicrometric powders obtained from freeze-dried precursors. In order to improve the cathode performance, three different electrode architectures have been proposed: (i) powder cathodes obtained by conventional screen-printing and sintering, and cathodes deposited by spray-pyrolysis on: (ii) as-prepared electrolyte surfaces and (iii) porous electrolyte backbones. The cathode activity for the oxygen reduction reaction has been investigated as a function of the microstructure and the sintering temperature. The microstructural optimization of the cathodes and the low fabrication temperature minimize the instability problems between the electrolyte and the cathode materials, leading to polarization resistances as low as 0.14 U cm2 at 600 C.MINECO (Ministerio de Economía y Competitividad), MAT2016-77648-R y EC2014-53906-

Durability and performance of CGO barriers and LSCF cathode deposited by spray-pyrolysis

Ce0.9Gd0.1O1.95 (CGO) protective layers are prepared by two different methods to prevent the reaction between the Zr0.84Y0.16O1.92 (YSZ) electrolyte and the La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode. In the first method, the CGO layers are deposited by an airbrushing technique from an ink containing CGO particles without and with cobalt as sintering aids. The second strategy consists in preparing both a dense CGO barrier layer and a porous LSCF cathode by spray-pyrolysis deposition, in order to further reduce the fabrication temperature and minimize the reaction between the cell components. The samples prepared by spray-pyrolysis exhibit better performance and durability than those obtained by conventional sintering methods. The results suggest that the interfacial reactivity between YSZ and LSCF as well as the Sr-enrichment at the cathode surface can be avoided by using low-temperature fabrication methods and by operating at temperatures lower than 650 °C.Ministerio de Ciencia e Innovación, EC2014-53906-R y MAT2016-77648-

Modification of the Microstructure and Transport Properties of La2CuO4−δ Electrodes via Halogenation Routes

dos Santos-Gómez L, Zamudio-García J, Porras-Vázquez JM, R. Losilla E, Marrero-López D. Modification of the Microstructure and Transport Properties of La2CuO4−δ Electrodes via Halogenation Routes. Processes. 2022; 10(6):1206. https://doi.org/10.3390/pr10061206This work was supported by the Ministerio de Economía, Industria y Competitividad from Spain (RTI2018-093735-B-I00 and PID2019-110249RB-I00) and Junta de Andalucía (UMA18-FEDERJA-033).This work was supported by the Ministerio de Economía, Industria y Competitividad from Spain (RTI2018-093735-B-I00 and PID2019-110249RB-I00) and Junta de Andalucía (UMA18-FEDERJA-033)

Design and optimization of self-assembled nanocomposite electrodes for SOFCs.

Nanocomposites exhibit improved electrochemical and mechanical properties compared to single-phase mate- rials, making them promising for the development of efficient and durable electrodes in solid oxide fuel cells (SOFCs). However, conventional fabrication methods usually involve multiple steps and high sintering tem- peratures, potentially leading to adverse effects on the properties of these materials due to excessive grain growth or reactivity among the cell components. In this study, nanocomposite electrodes of Sm0.5Sr0.5CoO3-δ - Ce0.9Sm0.1O1.95 (SSC–CSO) are prepared using a co-synthesis freeze-drying method, followed by screen-printing deposition and sintering at high temperatures. Alternatively, they are prepared through direct spray-pyrolysis deposition on the electrolyte at reduced temperatures. In both cases, the intimate mixture of SSC and CSO phases not only partially suppresses grain growth but also provides extended actives sites for the electrochemicalFunding for open access charge: Universidad de Málaga / CBUA This work was funded by MCIN/AEI/10.13039/501100011033/ FEDER-UE, through PID2021-126009OB-I00 and TED2021- 129836B–I00 projects. LdSG gratefully acknowledge the Universidad de Málaga for the funding through the JA.B1-20 projec

Symmetrical solid oxide fuel cells based on titanate nanocomposite electrodes

Nanocomposite electrodes of (Sr0.7Pr0.3)0.95TiO3±δ−Ce0.9Gd0.1O1.95 are directly prepared by spray-pyrolysis deposition on Zr0.82Y0.16O1.92 electrolytes and their properties are compared with those obtained by the traditional screen-printing powder method. The structural, microstructural and electrical characteristics are investigated for their potential use as both cathode and anode in Solid Oxide Fuel Cells. The nanocomposite electrodes with reduced particle size ∼30 nm achieved a polarization resistance at 700 ºC of 0.50 and 0.46 Ω cm2 in air and pure H2, respectively, outperforming those obtained for the analogous screen-printed electrodes with particle size of 450 nm, i.e. 4.8 and 3.9 Ω cm2, respectively. An electrolyte-supported cell with symmetrical electrodes reached a maximum and stable power density of 354 mW cm-2 at 800 ºC. These results demonstrate that the performance of electrode materials with modest electrochemical properties but high phase stability, such as doped-SrTiO3, can be highly improved by preparing nanocomposite electrodes directly on the electrolyte surface.This work was funded by PID2021–126009OB-I00 and PID2019–110249RB-I00 (Ministerio de Ciencia, Innovación y Universidades) and UMA18-FEDERJA-033 (Junta de Andalucia, Spain/FEDER) research projects. JZG thanks the Ministerio de Ciencia, Innovación y Universidades for his FPU grant (FPU17/02621. Funding for open access charge: Universidad de Málaga/CBUA.

Highly oriented and fully dense CGO films prepared by spray-pyrolysis and different precursor salts.

CeO2–based thin films are prepared by spray-pyrolysis deposition from different aqueous precursor solutions containing nitrate, chloride or acetate salts. The morphology and orientation growth strongly depends on the precursor type. Acetate solutions lead to dense films with improved microstructural features, i.e. uniform film thickness and a low roughness of 1.5 nm. Films with different Gd-content (Ce1-xGdxO2-x/2, 0≤x≤0.2, CGO) are prepared from acetate salts. These films show a (200) preferred orientation growth, regardless of the substrate type, i.e. fused quartz and polycrystalline ceramics. The in-plane conductivity of the films on quartz is lower than that of the bulk material, possibly due to the different thermal mismatch between the substrate and the film. These CGO films are also evaluated as protective layers to prevent the reaction between the Zr0.84Y0.16O1.92 (YSZ) electrolyte and the La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode. The electrode efficiency of LCSF improves greatly after the introduction of a 150 nm thin CGO interlaye

Comparison of surface integral equation formulations for electromagnetic analysis of plasmonic nanoscatterers

The performance of most widespread surface integral equation (SIE) formulations with the method of moments (MoM) are studied in the context of plasmonic materials. Although not yet widespread in optics, SIE-MoM approaches bring important advantages for the rigorous analysis of penetrable plasmonic bodies. Criteria such as accuracy in near and far field calculations, iterative convergence and reliability are addressed to assess the suitability of these formulations in the field of plasmonics.Ministerio de Ciencia e Innovación | Ref. TEC2011-28784-C02-01Ministerio de Ciencia e Innovación | Ref. TEC2011-28784-C02-0

One step synthesis of nanocomposite electrodes for reversible electrochemical cells.

The irregular and seasonal disposition of renewable energy requires advanced devices for energy storage and conversion. Reversible electrochemical cells can address this approach by operating as both electrolyzer and fuel cell in an efficient and eco-friendly way. An important issue for increasing the performance of ceramic electrochemical cells is the sluggish oxygen reduction reaction kinetic at the air electrode [1]. It is well known that the efficiency of air electrodes may be improved by adding a second phase with high ionic conductivity, i.e. doped-CeO2 and Bi2O3, to obtain a composite electrode.[1] Moreover, they are usually employed to reduce the mechanical stress between electrode and electrolyte layers, originated by their different thermal expansion coefficients, thus enhancing the mechanical stability of the cell. Traditionally, composite electrodes are prepared by mechanically mixing pristine materials but, unfortunately, it is difficult to control the composition distribution and architecture with this method. In this work, different nanocomposite electrodes are successfully prepared by using both the freeze-drying powder precursor method and the spray-pyrolysis deposition, in a single-step synthesis, from precursor solutions containing all cations in stoichiometric amounts. For instance, La0.8Sr0.2MnO3-δ-Ce0.9Gd0.1O1.95 (LSM-CGO), La0.6Sr0.4Co0.2Fe0.8O3-δ-Ce0.9Gd0.1O1.95 (LSCF-CGO) and Sm0.5Sr0.5CoO3-δ-Ce0.9Sm0.1O1.95 (SSC-CSO). Both fluorite and perovskite-based phases are formed simultaneously, reducing drastically the preparation time, which is crucial for potential industrial application. The electrodes are composed of nanometric particles, providing high active area for electrochemical reactions. The intimate mixture of two immiscible phases hinder the cation diffusion and the grain growth rate. Very low polarization resistance values are obtained, i.e. 0.088 Ω cm2 at 700 °C for SSC-CSO.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Sm0.5Sr0.5CoO3-δ - Ce0.9Sm0.1O1.95 nanocomposites for reversible electrochemical cells.

The generation of electricity through environmentally friendly sources of energy has been one of the main challenges of our society in the last decades. Nevertheless, the irregular and seasonal disposition of renewable energy requires devices for energy storage and conversion. Reversible electrochemical cells can address this approach by operating as an electrolyser, when an excess of electricity is available, and as a fuel cell, when the electricity is needed afterwards [1]. The efficiency of air electrodes with poor ionic conductivity may be improved by adding a second phase with high ionic conductivity, i.e. CeO2 and Bi2O3-based electrolytes. Many studies have shown that composite electrodes have higher efficiency than the single-phase ones due to the increased active area [2]. Traditionally, composite electrodes are prepared by mechanically mixing the pristine materials but, unfortunately, it is difficult to control the composition distribution with this method. In this work, Sm0.5Sr0.5CoO3-δ-Ce0.9Sm0.1O1.95 (SSC-CSO) nanocomposite cathodes are successfully prepared in a single process by using the freeze-drying precursor method, in a single-step synthesis, from a precursor solution containing all cations in stoichiometric amounts. SSC and CSO are formed simultaneously, reducing the preparation time, which is an important improvement for industrial application. Different percentages of SSC-CSO are investigated: 100-SSC, 80-SSC, 60-SSC and 50-SSC. The electrode is composed of nanometric particles, providing high active area for the electrochemical reactions. The CGO addition suppresses the grain growth of the nanocomposite cathodes, rendering lower particle size, from 0.53 to 0.32 nm of diameter for 100-SSC to 50-SSC, respectively. This is explained by the presence of CGO as secondary phase, which limits the cation diffusion and the grain growth rate. A low polarization resistance of 0.088 Ω cm2 is obtained at 700 °C for 50-SSC.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech