Estrutura eletrônica de derivados de C60 para aplicações em células solares orgânicas

• Ano de defesa: 2014
• Autor(a) principal: Ferreira, Rodrigo Marques [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Celulas solares; Energia - Fontes alternativas; Eletrons; Solar cells
• Link de acesso: http://hdl.handle.net/11449/110883

Today, there is a great demand in the development of new energy resources. One of the possible alternatives for energy production are solar cells and, among them, organic solar cells. They still have low efficiency in energy conversion, therefore a lot of research has been conducted in order to improve their characteristics. In this work we studied the electron acceptor components, used in the active layer of organic solar cells, specifically those formed by C60 and its derivatives, which have been widely studied because their good charge transport properties. These studies mainly aim at adjusting the electronic levels, thus enabling the increase of the open circuit voltage and increasing the efficiency of energy conversion. In this work we propose a methodology that provides good results in the representation of the structural and electronic properties of the systems hereby studied. This methodology is a mix of semiempirical and ab initio theory levels. We also investigated methods to correlate the electronic properties of materials studied with the open circuit voltage, as this is directly linked to the efficiency of organic solar cells. Through this work we found a method to simulate the open-circuit voltage with a medium deviation of 13%. And finally, we investigate possible chemical substitutions on the C60 derivatives. From this study, we observed patterns in electron levels behavior caused according to the type of the substituent