Estudo da dopagem de GO em TiO2 para aplicação em células solares de terceira geração

• Autor(a) principal: Rodrigues, Matheus Freitas
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações do Mackenzie
• Texto Completo: http://dspace.mackenzie.br/handle/10899/26509
• topic: energia solar; células fotovoltáicas; pasta de TiO2; óxido de grafeno reduzido; eficiência energética; CNPQ::ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA

Electrical energy is fundamental to the modern man’s daily life and it is carried out in many activities’ day by day. One of the techniques that man has developed to convert the energy coming from the Sun into electrical energy consists of the so-called photovoltaic solar cells. Solar energy represents a renewable source because the constant emission of solar radiation acts as a inexhaustible resource, besides being also considered a clean energy’s source, since its operation does not imply the emission of polluting products. Brazil has great potential to invest in a solar energy plan due to its extension and location near the Equator. In recent years, the cost of solar energy has fallen by about 50% in recent years and by 70% in the last decade due to the technological innovations achieved in the sector. The present work objectives are evaluating the effect of mixing the semiconductor material present in a solar cell (TiO2) with nanocomposites based on graphene oxide (GO). The GO was obtained by the modified Hummers method and it was converted to reduced graphene oxide (r-GO) by using thermal treatments carried out at different temperatures, 100°C (212°F) and 200°C (392°F), using loads of 1%, 2% and 3% by weight of material. Both the isolated materials and their mixture were characterized by using X-ray diffraction (XRD) and infrared spectroscopy. The main results show that the GO conversion into r-GO best happened at a temperature of 200 °C and with a concentration of 3% by weight of GO mixed with the TiO2 paste, due to a better removal of the oxygen groups formed together with the GO obtained, avoiding the degradation of the paste by the GO concentration. The conversion of GO to r-GO is very important because the last one shows better photovoltaic properties comparing to the first one, allowing it to reach the objectives proposed in the present work.