Sanat Eğitiminde Fiziksel Yapı ve Araç Gereç Kullanımı

Realizar estudos de óxidos com estrutura perovskita La1-xAxCoO3 dopadas com Bário e

Cálcio com x=0,2, usando a técnica Pechini na preparação dessas estruturas policristalinas. A técnica utilizada para investigar essas estruturas na faixa de temperatura entre 50 K a 298 K será a espectroscopia de absorção de raios X (XAS) na borda K do cobalto. Estas análises nesses materiais têm como finalidade observar se a estrutura La1-xAxCoO3 dopadas Ba e Ca em função

de temperatura mostram as mesmas características estruturais nessas amostras em relação aos estudos desenvolvidos neste trabalho com a técnica de combustão. Assim como também, verificar se as anomalias apresentadas na estrutura La0,8Ba0,2CoO3 nas temperaturas 220 K e 260

K são características intrínseca desse material, ou surgem dos diferentes métodos de preparação dessas amostras. Propõe-se, também, estudar mais detalhadamente na região XANES, através de estudos teóricos quantitativos, as transições de spin nas estruturas La0,8Ba0,2CoO3 e

La0,8Ca0,2CoO3 em função de temperatura sintetizadas pelas técnicas combustão e Pechinni.

Outra possibilidade de trabalho futuro é estudar as propriedades magnéticas dessas amostras para possível aplicação futura.

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