Síntese e Caracterização deTiO2 Puro e TiO2 Modificado com Zr-MOF: Potencial para Aplicação em Células Solares
Data
2022-12-15
Autores
Oliveira, Karine Vilares de 
Orientadores
Mazzo, Tatiana Martelli
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Impactos causados pela revolução industrial e a crescente preocupação com as questões ambientais fomentam a procura por matrizes energéticas sustentáveis. Diante deste desafio a energia fotovoltaica apresenta grande potencial para o fornecimento de energia limpa. A fim de obter maior eficiência ao menor custo possível a procura por materiais que atendam esses critérios vêm sendo pesquisados e testados. O dióxido de titânio (TiO2) apresenta grande potencial semicondutor, no entanto possui limitada capacidade de absorção de luz. As MOFs (metal-organic frameworks) possuem características promissoras para a melhora da atividade fotovoltaica do TiO2. O presente trabalho teve como objetivo analisar o potencial fotovoltaico do TiO2 puro e modificado com Zr-MOF através da síntese e caracterização destes materiais. O método utilizado para a síntese do TiO2 foi o sol-gel por apresentar vantagens como a obtenção de um material mais homogêneo e puro e com poucos defeitos cristalinos. Para a síntese do Zr-MOF utilizou-se o método solvotérmico que também oferece benefícios como a obtenção de partículas com maior uniformidade em sua composição e não requerer tratamentos térmicos a altas temperaturas posteriormente à síntese. Os materiais foram caracterizados pelas técnicas de difração de raios X (DRX), microscopia eletrônica de varredura com emissão de campo (MEV-FEG) e a propriedade fotoeletroquímica foi avaliada por voltametria linear (VL) e espectroscopia de impedância eletroquímica (EIE). A técnica de DRX mostrou que os métodos de síntese utilizados foram eficientes para obtenção dos materiais livres de fase secundárias, pela microscopia nota-se que foram obtidas nanopartículas sendo o TiO2 no formato esférico e aglomerado e o Zr-MOF no formato octaédrico, pela VL e pela EIE observou-se que o material TiO2 quando modificado com a inserção de 50% de Zr-MOF ocasiona melhoria significativa em sua propriedade fotoeletroquímica.
Impacts caused by the industrial revolution and a growing concern with environmental issues foster the search for energy matrices. Faced with this challenge, photovoltaic energy has great potential for providing clean energy. In order to obtain greater efficiency at the lowest possible cost, the search for materials that meet these criteria has been researched and tested. Titanium dioxide (TiO2) has great semiconductor potential, however it has limited light absorption capacity. MOFs (metal-organic frameworks) have promising characteristics for improving the photovoltaic activity of TiO2. The present work aimed to analyze the photovoltaic potential of pure TiO2 and modified with Zr-MOF through the synthesis and characterization of these materials. The method used for the synthesis of TiO2 was the sol-gel because it presents advantages such as obtaining a more homogeneous and pure material with few crystalline defects. For the synthesis of Zr-MOF, the solvothermal method was used, which also offers benefits such as obtaining particles with greater uniformity in their composition and not requiring thermal treatments at high temperatures after synthesis. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy with field transmission (SEM-FEG) and the photoelectrochemical property was evaluated by linear voltammetry (VL) and electrochemical impedance spectroscopy (EIS). The XRD technique showed that the synthesis methods used were efficient to obtain materials free of secondary phase, by microscopy it is noted that nanoparticles were obtained, TiO2 in spherical and agglomerated format and Zr-MOF in octahedral format, by VL and by EIE it was observed that the TiO2 material when modified with the insertion of 50% Zr-MOF causes significant improvement in its photoelectrochemical property.
Impacts caused by the industrial revolution and a growing concern with environmental issues foster the search for energy matrices. Faced with this challenge, photovoltaic energy has great potential for providing clean energy. In order to obtain greater efficiency at the lowest possible cost, the search for materials that meet these criteria has been researched and tested. Titanium dioxide (TiO2) has great semiconductor potential, however it has limited light absorption capacity. MOFs (metal-organic frameworks) have promising characteristics for improving the photovoltaic activity of TiO2. The present work aimed to analyze the photovoltaic potential of pure TiO2 and modified with Zr-MOF through the synthesis and characterization of these materials. The method used for the synthesis of TiO2 was the sol-gel because it presents advantages such as obtaining a more homogeneous and pure material with few crystalline defects. For the synthesis of Zr-MOF, the solvothermal method was used, which also offers benefits such as obtaining particles with greater uniformity in their composition and not requiring thermal treatments at high temperatures after synthesis. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy with field transmission (SEM-FEG) and the photoelectrochemical property was evaluated by linear voltammetry (VL) and electrochemical impedance spectroscopy (EIS). The XRD technique showed that the synthesis methods used were efficient to obtain materials free of secondary phase, by microscopy it is noted that nanoparticles were obtained, TiO2 in spherical and agglomerated format and Zr-MOF in octahedral format, by VL and by EIE it was observed that the TiO2 material when modified with the insertion of 50% Zr-MOF causes significant improvement in its photoelectrochemical property.
Descrição
Citação
OLIVEIRA, Karine Vilares de. Síntese e Caracterização deTiO2 Puro e TiO2 Modificado com Zr-MOF: Potencial para Aplicação em Células Solares. 2022. 32 f. Trabalho de conclusão de curso (Graduação em Bacharelado Interdisciplinar em Ciência e Tecnologia do Mar) - Instituto do Mar, Universidade Federal de São Paulo, Santos, 2022.