The preparation of luminescent and reversible thermochromic Mn-doped Ca-Zn-Al-O inorganic materials

In this research, we reported the thermochromic and luminescent behaviors of Ca14Zn6Al10-xMn4O35 (x = 0,0.5,1.0,1.5,2) garnet materials prepared by a high-temperature solid-state reaction method. Thermochromism of all samples showed gradual tunability of color with a change in temperature. However, the optimal thermochromic performance was observed for Ca14Zn6Al10-xMnxO35 samples with x = 1 and the sintering temperature of 1200 degrees C. The resultant samples showed a reversible change in color from yellow to reddish yellow when heated to around 500 degrees C. This was due to the changes in absorption bands of Mn4+ and Mn5+ in octahedral and tetrahedral sites, respectively. The materials also exhibited a deep red emission at around 710 nm. The existence of impurity phases was found to degrade the optical properties of the samples.

Automated summary

This research investigated the thermochromic and luminescent properties of Ca14Zn6Al10-xMn4O35 (x = 0, 0.5, 1.0, 1.5, 2) garnet materials prepared by a high-temperature solid-state reaction method. The samples exhibited tunable color changes with a change in temperature, with the best thermochromic performance observed for Ca14Zn6Al10-xMnxO35 samples with x = 1 and a sintering temperature of 1200 degrees C. The reversible change in color from yellow to reddish yellow was attributed to the changes in absorption bands of Mn4+ and Mn5+ in different crystal sites. The presence of impurity phases was found to affect the optical properties of the samples.