Zinc-gallium oxynitride powders: effect of the oxide precursor synthesis route (Pós de oxinitreto de zinco e gálio: efeito da rota de síntese do óxido precursor)
نویسندگان
چکیده
Zinc-gallium oxynitride powders (ZnGaON) were synthesized by nitridation of ZnGa2O4 oxide precursor obtained by polymeric precursors (PP) and solid state reaction (SSR) methods and the influence of the synthesis route of ZnGa2O4 on the final compound ZnGaON was investigated. Crystalline single phase ZnGa2O4 was obtained at 1100 oC / 12 h by SSR and at 600 oC / 2 h by PP with different grain sizes and specific surface areas according to the synthesis route. After nitridation, ZnGaON oxynitrides with a GaN würtzite-type structure were obtained in both cases, however at lower temperatures for PP samples. The microstructure and the specific surface area were strongly dependent on the oxide synthesis method and on the nitridation temperature (42 m2g-1 and 5 m2g-1 for PP and SSR oxides treated at 700 °C, respectively). The composition analyses showed a strong loss of Zn for the PP samples, favored by the increase of ammonolysis temperature and by the higher specific surface area.
منابع مشابه
Comunication Zinc supplementation , production and quality of coffee beans
Apesar da importância do zinco na nutrição do cafeeiro, quase não há informações que relacionem o suprimento de zinco e a qualidade dos grãos. Este trabalho avaliou o efeito de zinco sobre a produção e a qualidade dos grãos de café. O experimento foi conduzido com Coffea arabica L. na Zona da Mata de Minas Gerais, Brasil. O delineamento utilizado foi inteiramente ao acaso, com dois tratamentos:...
متن کاملSeparation and Pre-concentration of Cadmium, Copper, Lead, Nickel and Zinc by Solid-Liquid Extraction of their Cocrystallized Naphthalene Dithizone Chelate in Saline Matrices
Um procedimento em batelada é proposto para separação e pré-concentração de cádmio, chumbo, níquel e zinco em amostras de salmoura. O método baseia-se na adsorção dos íons metálicos sobre a fase sólida composta de ditizona co-cristalizada com naftaleno microcristalino, na faixa de pH de 8,5 – 9,1. Ácido nítrico é utilizado para re-extrair os cátions da fase sólida, os quais são determinados por...
متن کاملInfluence of the spatulation of two zinc oxide-eugenol-based sealers on the obturation of lateral canals Influência da espatulação de dois cimentos à base de óxido de zinco e eugenol na obturação de canais laterais
The objective of this research was to evaluate, in vitro, the importance of the correct manipulation of endodontic sealers, correlating it with flow rate and with the consequent obturation of root canals. Twenty-four human canines were prepared, 1 mm from the apex, with K-files up to size 50, by means of the step-back technique. Six lateral canals were then drilled in each tooth, with size 10 f...
متن کاملStudies of Zinc(II) in Pharmaceutical and Biological Samples by Extractive Spectrophotometry: Using Pyridoxal-4-phenyl-3-thiosemicarbazone as Chelating Reagent
Piridoxal-4-fenil-3-tiossemicarbazona (PPT) é proposto como um novo reagente sensível para a determinação espectrofotométrica de zinco(II). PPT reage com zinco(II) no intervalo de pH entre 5,0 e 6,0, para formar um complexo colorido amarelo, o qual foi adequadamente extraído em n-butanol. A absorbância do complexo Zn(II)-PPT foi medida em diferentes intervalos de tempo, a 430 nm, para averiguar...
متن کاملSynthesis and characterization of a Bi-Oxide nanoparticle ZnO/CuO by thermal decomposition of oxalate precursor method
In the present work, we report the synthesis of binary nano metal oxides such as Zinc /Copper Oxide via novel dry synthetic methods such as thermal decomposition of oxalate precursor. The synthesis route involves facile solid-phase mechanochemical activation of a physical mixture of simple copper/zinc salts and oxalic acid, followed by calcination of the as-ground oxalate precursors at 450◦C. X...
متن کامل