Mechanical force induced luminescence ratiometric thermometry in CaZnOS:Dy3+

The 4 I 15/2 - 6 H 15/2 and 4 F 9/2 - 6 H 15/2 transitions of Dy 3+ are usually used for luminescent ratiometric thermometry in the form of photoluminescence. However, here we demonstrate the possibility of using this pair of lines for luminescent ratiometric thermometry in the model of mechanoluminescence (ML) in CaZnOS:Dy 3+ . Upon stimulation of an external mechanical force rather than light, CaZnOS:Dy 3+ emits bright yellow luminescence. The intensity ratio of 4 I 15/2 - 6 H 15/2 to 4 F 9/2 - 6 H 15/2 transitions of Dy 3+ is found to increase gradually with the rise of temperature, which makes Dy 3+ a qualified temperature indicator. Our work enriches the family of optical thermometry.