Xerogeles de carbono como material de electrodo en dispositivos electroquímicos

[EN] The ability to tailor the porous characteristics of carbon xerogels makes them potential candidates for use in a wide variety of applications, one of which as electrode materials in electrochemical devices (supercapacitors, lithium-ion batteries or fuel cells). These systems are attracting a lo...

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Detalles Bibliográficos
Autor: Canal Rodríguez, María
Tipo de recurso: tesis doctoral
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/177903
Acceso en línea:http://hdl.handle.net/10261/177903
Access Level:acceso abierto
Palabra clave:Xerogel
Carbono
Aerogeles
Supercondensador
Baterías de Ión-Litio
ORR
Electroquímica
Descripción
Sumario:[EN] The ability to tailor the porous characteristics of carbon xerogels makes them potential candidates for use in a wide variety of applications, one of which as electrode materials in electrochemical devices (supercapacitors, lithium-ion batteries or fuel cells). These systems are attracting a lot of attention nowadays firstly, because of the continuous development of technology caused by the increasing use of electronical devices, and secondly, due to the need to reduce the use of fossil fuels in favour of cleaner and more sustainable forms of energy generation. However, to ensure their optimal performance, in addition to a tailored porosity, the electrode material in such devices needs to have a high electrical conductivity. An objective that is not easy to reach as they are normally opposite characteristics in carbon materials. In the present Doctoral Thesis three strategies were employed: (i) the addition of conductive additives to the carbonaceous structure in order to form a conductive network that facilitates the movement of electrons while preserving the control of porosity in carbon xerogels (i.e. hybrid xerogels), (ii) the graphitization or structural ordering of carbon xerogels under conventional heating and microwave heating and (iii) the graphitization of hybrid carbon xerogels. By adjusting the variables that influence the different techniques employed, it was possible to obtain carbon xerogels that combine a high volume of pores in the micro and macroporosity range and a high electrical conductivity. The materials synthesized were evaluated as electrodes in aqueous supercapacitors (i) in lithium-ion batteries (ii and iii) and as catalysts in the oxygen reduction reaction (ii), with good results in each case, especially in the case of supercapacitors in which at high current densities, greater energy and power densities than those of the commercial material analysed under the same conditions were obtained.