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Structural and Spectroscopic Study of a New Pink Chromium‐Free Er 2 (Ti,Zr) 2 O 7 Ceramic Pigment
Author(s) -
Martos Mónica,
JuliánLópez Beatriz,
Cordoncillo Eloisa,
Escribano Purificación
Publication year - 2009
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2009.03335.x
Subject(s) - pyrochlore , materials science , fluorite , differential thermal analysis , raman spectroscopy , stoichiometry , thermogravimetric analysis , ceramic , thermal analysis , lanthanide , crystallography , phase (matter) , ion , analytical chemistry (journal) , diffraction , chemistry , thermal , metallurgy , optics , physics , organic chemistry , chromatography , meteorology
Transition metal ions are usually incorporated as chromophores into pyrochlore structures in order to develop colored compounds. However, due to the high toxicity of some of them (Cr, Ni, Co, Cd …), other nontoxic species such as lanthanide ions have been studied in order to produce environment‐friendly pigments. This paper describes the structural and spectroscopic study of a pink pigment based on the Er 2 Ti 2− x Zr x O 7 system synthesized by a sol–gel route. A previous research on the Er 2 Ti 2 O 7 system revealed that this compound exhibits a pink coloration only in its defect fluorite‐type structure. At high temperature (800°C), an atomic rearrangement into a pyrochlore network significantly reduces its coloration. The stabilization of the fluorite phase in Er 2 Ti 2 O 7 through substitution of Ti(IV) with larger Zr(IV) ions is studied in this work. The analysis by differential thermal analysis and thermogravimetric analysis, X‐ray powder diffraction, and Raman techniques indicates that the introduction of Zr(IV) species successfully avoids the undesired fluorite‐to‐pyrochlore transition. The colorimetric study concludes that the optimal composition corresponds to the Er 2 Ti 0.6 Zr 1.4 O 7 stoichiometry, which gives an intense pink coloration independently of the thermal treatment. This study introduces a novel nontoxic pigment suitable for industrial applications at both low‐ and high‐temperature ceramic technologies.