Disipación de energía en dispositivos electrónicos y gestión de calor avanzada

Uno de los mayores desafíos de nuestra sociedad está relacionada con el consumo, la disipación y el desperdicio de energía. Un ejemplo destacado es el de la electrónica integrada, donde los problemas de disipación de energía han limitado su rendimiento. En la primera parte de la presentación, se habla sobre la disipación de energía en dispositivos electrónicos, como transistores basados en materiales 2D o en memorias resistivas de acceso aleatorio (RRAM). Por un lado, el uso de materiales 2D, como MoS2, representan nuevas oportunidades para la industria electrónica. Sin embargo, comprender sus propiedades térmicas, como la conductividad o resistencia térmica de contacto, es esencial para lograr una disipación de energía eficiente y evitar un rendimiento limitado debido al sobrecalentamiento. Por otro lado, conocer la temperatura que alcanzan los filamentos conductores en memorias RRAM es esencial para diseñar y mejorar el funcionamiento de estos dispositivos. No obstante, su caracterización experimental ha sido un desafío de larga duración debido a que el calentamiento del filamento está localizado en la nano-escala. En paralelo, la gestión avanzada del calor disipado por estos sistemas para su posterior conversión o almacenamiento, podría tener un importante impacto tecnológico. En la segunda parte de mi presentación, se presentan dispositivos térmicos de estado sólido capaces de controlar el calor de una forma análoga a como los dispositivos electrónicos controlan la electricidad. En este contexto, se da un ejemplo de diodo térmico que puede ser usado en aplicaciones de almacenamiento de energíaUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Transport Property Measurements of Nanostructured Materials

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física de la Materia Condensada. Fecha de lectura: 14-07-2015La realización de esta tesis doctoral ha sido posible gracias a la financiación del proyecto Europeo ERC StG NanoTEC 240497 y a la concesión de una beca JAE Pre-Doc del CSIC

Structure, Composition, Transport Properties, and Electrochemical Performance of the Electrode‐Electrolyte Interphase in Non‐Aqueous Na‐Ion Batteries

Rechargeable Li-ion battery technology has progressed due to the development of a suitable combination of electroactive materials, binders, electrolytes, additives, and electrochemical cycling protocols that resulted in the formation of a stable electrode-electrolyte interphase. It is expected that Na-ion technology will attain a position comparable to Li-ion batteries dependent on advancements in establishing a stable electrode-electrolyte interphase. However, Li and Na are both alkali metals with similar characteristics, yet the physicochemical properties of these systems differ. For this reason, a detailed study on the electrode-electrolyte interphase properties, composition, and structure is required to understand the factors that influence the battery\u27s behavior. Herein, the research that has been performed on the electrode-electrolyte interphase for both anode and cathode in the most important families of electrode materials, including carbonate ester-based and advanced electrolytes such as ether-based carbonates and ionic liquids is presented

Influence of the Current Density on the Interfacial Reactivity of Layered Oxide Cathodes for Sodium‐Ion Batteries

The full commercialization of sodium-ion batteries (SIBs) is still hindered by their lower electrochemical performance and higher cost ($ W-1 h(-1)) with respect to lithium-ion batteries. Understanding the electrode-electrolyte interphase formation in both electrodes (anode and cathode) is crucial to increase the cell performance and, ultimately, reduce the cost. Herein, a step forward regarding the study of the cathode-electrolyte interphase (CEI) by means of X-ray photoelectron spectroscopy (XPS) has been carried out by correlating the formation of the CEI on the P2-Na0.67Mn0.8Ti0.2O2 layered oxide cathode with the cycling rate. The results reveal that the applied current density affects the concentration of the formed interphase species, as well as the thickness of CEI, but not its chemistry, indicating that the electrode-electrolyte interfacial reactivity is mainly driven by thermodynamic factors.The authors would like to thank B. Acebedo for her support with materials synthesis, characterization, and testing, and E. Gonzalo for the fruitful discussions. M.Z. thanks the Basque Government for her Post-doc fellowship (POS_2017_1_0006). HIU authors (M.Z and S.P.) acknowledge the Helmholtz Association Basic funding. Open Access Funding provided by Universita degli Studi di Camerino within the CRUI-CARE Agreement

Structure, Composition, Transport Properties, and Electrochemical Performance of the Electrode-Electrolyte Interphase in Non-Aqueous Na-Ion Batteries

[EN] Rechargeable Li-ion battery technology has progressed due to the development of a suitable combination of electroactive materials, binders, electrolytes, additives, and electrochemical cycling protocols that resulted in the formation of a stable electrode-electrolyte interphase. It is expected that Na-ion technology will attain a position comparable to Li-ion batteries dependent on advancements in establishing a stable electrode-electrolyte interphase. However, Li and Na are both alkali metals with similar characteristics, yet the physicochemical properties of these systems differ. For this reason, a detailed study on the electrode-electrolyte interphase properties, composition, and structure is required to understand the factors that influence the battery's behavior. Herein, the research that has been performed on the electrode-electrolyte interphase for both anode and cathode in the most important families of electrode materials, including carbonate ester-based and advanced electrolytes such as ether-based carbonates and ionic liquids is presented.Ministerio de Ciencia, Innovación y Universidades. Grant Number: PID2019- 107468RB-C21 Gobierno Vasco Eusko Jaurlaritza. Grant Number: IT1226-1

Influence of the Current Density on the Interfacial Reactivity of Layered Oxide Cathodes for Sodium-Ion Batteries

The full commercialization of sodium-ion batteries (SIBs) is still hindered by their lower electrochemical performance and higher cost ($ W-1 h(-1)) with respect to lithium-ion batteries. Understanding the electrode-electrolyte interphase formation in both electrodes (anode and cathode) is crucial to increase the cell performance and, ultimately, reduce the cost. Herein, a step forward regarding the study of the cathode-electrolyte interphase (CEI) by means of X-ray photoelectron spectroscopy (XPS) has been carried out by correlating the formation of the CEI on the P2-Na0.67Mn0.8Ti0.2O2 layered oxide cathode with the cycling rate. The results reveal that the applied current density affects the concentration of the formed interphase species, as well as the thickness of CEI, but not its chemistry, indicating that the electrode-electrolyte interfacial reactivity is mainly driven by thermodynamic factors.The authors would like to thank B. Acebedo for her support with materials synthesis, characterization, and testing, and E. Gonzalo for the fruitful discussions. M.Z. thanks the Basque Government for her Post-doc fellowship (POS_2017_1_0006). HIU authors (M.Z and S.P.) acknowledge the Helmholtz Association Basic funding. Open Access Funding provided by Universita degli Studi di Camerino within the CRUI-CARE Agreement

Thermal conductivity reduction in thermoelectric nanowires

Comunicación presentada en la 12th European Conference on Thermoelectricity (ECT2014), celebrada en Madrid del 24 al 26 de septiembre de 2014.Peer Reviewe