The development of pigments imparting new hues to both ceramic bodies and glazes is a pressing need worldwide and a highly active field of research. A new family of ceramic pigments based on the perovskite structure YAl(1-x)CrxO3 (xCr-YAP) have been investigated as promising system for the development of colours ranging from red to green with the variation of Cr content. Pure Cr-YAP pigments are highly refractory and environmentally-friendly, but difficult to synthesized due to the simultaneous formation of other phases as YAG (Y3All5O12) and YAM (Y4All2O9). The aim of this study was the synthesis of pure Cr-YAP pigments with different Cr content (0.035 < x <0.5). For this purpose, a water-based sol-gel combustion synthesis was optimized and the results were compared with those obtained by solid state processing. The pigment precursors evolution was investigated through TG/DTA, FTIR, DRS and XRPD. TG-DTA and FTIR analysis confirmed that the strong exothermic reaction, induced by citrate and nitrate species, occurred at low temperature while XRPD data evidenced a strong correlation between Cr amount in the materials and YAP phase formation. Moreover, our results indicated a strong influence on YAP purity of synthesis conditions and gel-combustion rate, confirming the necessity to conserve the stoichiometry on an atomic scale during all the preparation process. Additional studies are ongoing to verify the possibility of utilizing a microwave heating system both for synthesis and combustion processes.
M. Blosi, S. Albonetti, A L. Costa, G. Cruciani, M. C. Dalconi, M. Dondi, et al. (2007). Sol-gel combustion synthesis of chromium doped YAP ceramic pigments. s.l : s.n.
Sol-gel combustion synthesis of chromium doped YAP ceramic pigments
BLOSI, MAGDA;ALBONETTI, STEFANIA;
2007
Abstract
The development of pigments imparting new hues to both ceramic bodies and glazes is a pressing need worldwide and a highly active field of research. A new family of ceramic pigments based on the perovskite structure YAl(1-x)CrxO3 (xCr-YAP) have been investigated as promising system for the development of colours ranging from red to green with the variation of Cr content. Pure Cr-YAP pigments are highly refractory and environmentally-friendly, but difficult to synthesized due to the simultaneous formation of other phases as YAG (Y3All5O12) and YAM (Y4All2O9). The aim of this study was the synthesis of pure Cr-YAP pigments with different Cr content (0.035 < x <0.5). For this purpose, a water-based sol-gel combustion synthesis was optimized and the results were compared with those obtained by solid state processing. The pigment precursors evolution was investigated through TG/DTA, FTIR, DRS and XRPD. TG-DTA and FTIR analysis confirmed that the strong exothermic reaction, induced by citrate and nitrate species, occurred at low temperature while XRPD data evidenced a strong correlation between Cr amount in the materials and YAP phase formation. Moreover, our results indicated a strong influence on YAP purity of synthesis conditions and gel-combustion rate, confirming the necessity to conserve the stoichiometry on an atomic scale during all the preparation process. Additional studies are ongoing to verify the possibility of utilizing a microwave heating system both for synthesis and combustion processes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
