Produção Nacional
Revisado por pares
Crystallization, mechanical, and optical properties of transparent, nanocrystalline gahnite glass‐ceramics
2017; Wiley; Volume: 100; Issue: 5 Linguagem: Inglês
10.1111/jace.14753
ISSN1551-2916
AutoresAtiar Rahaman Molla, Alisson Mendes Rodrigues, Shiv Prakash Singh, Ricardo F. Lancelotti, Edgar D. Zanotto, Ana Cândida Martins Rodrigues, M. Reza Dousti, Andréa Simone Stucchi de Camargo, Cláudio José Magon, Igor d’Anciães Almeida Silva,
Tópico(s)Luminescence Properties of Advanced Materials
ResumoAbstract This paper describes the preparation of a transparent glass‐ceramic from the SiO 2 ‐K 2 O‐ZnO‐Al 2 O 3 ‐TiO 2 system containing a single crystalline phase, gahnite (ZnAl 2 O 4 ). TiO 2 was used as a nucleating agent for the heat‐induced precipitation of gahnite crystals of 5‐10 nm. The evolution of the ZnAl 2 O 4 spinel structure through the gradual formation of Al‐O bonds was examined by infrared spectroscopy. The dark brown color of the transparent precursor glass and glass‐ceramic was eliminated using CeO 2 . The increase in transparency of the CeO 2 ‐doped glass and glass‐ceramics was demonstrated by UV ‐visible absorption spectroscopy. EPR measurements confirmed the presence of Ce 3+ ions, indicating that CeO 2 was effective in eliminating the brown color introduced by Ti 3+ ions via oxidation to Ti +4 . The hardness of the glass‐ceramic was 30% higher than that of the as‐prepared glasses. This work offers key guidelines to produce hard, transparent glass‐ceramics which may be potential candidates for a variety of technological applications, such as armor and display panels.
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