Dielectric properties of Bi-substituted LDHs synthesized by co-precipitation and sol-gel methods

• Autor(a) principal: Sokol, Denis
• Data de Publicação: 2019
• Outros Autores: Ivanov, Maksim, Salak, Andrei N., Grigalaitis, Robertas, Banys, Juras, Kareiva, Aivaras
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/26511
• topic: Layered double hydroxide; Bismuth substitution; Co-precipitation; Sol-gel; Dielectric properties

Magnesium-aluminum-bismuth layered double hydroxides (Mg3Al1-xBix; LDHs) were prepared using both coprecipitation and sol-gel methods. For the preparation of Mg/Al/Bi LDH by the co-precipitation method, the appropriate amounts of dissolved starting materials (Al(NO3)3 · 9H2O, Mg(NO3)2 · 6H2O and Bi(NO3)3 · 5H2O) were mixed with a solution of NaHCO3:NaOH. In the sol-gel processing, the precursor Mg-Al-Bi-O gels were synthesized using the same starting materials and ethylene glycol as complexing agent. The mixed-metal oxides obtained by subsequent heating of Mg-Al-Bi-O gels at 650 °C were reconstructed to Mg3Al1-xBix LDHs in water at 80 °C. All the synthesized products were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and dielectric measurements.