Optical temperature-sensitive hydrophobic membrane based on Eu(III)-doped yttrium oxide nanosheets

In this study, Eu(III)-doped yttrium oxide nanosheets were prepared after the dehydration and exfoliation of layered hydroxides. The morphologies of the as-prepared nanosheets were determined using transmission electron microscopy and atomic force microscopy. Positively charged Eu(III)-doped yttrium oxide nanosheets with α-thiophenylacetone trifluoride as antenna uniformly adhered to the surface of glass fiber membranes by layer-by-layer assembly technology with negatively charged polyacrylic acid. Thereafter, an optical temperature-sensitive hydrophobic membrane with a water contact angle of 124.35° ± 0.15° was obtained. In air and water environments, both the lifetime and luminescence intensity of the as-prepared fluorescent temperature-sensing membrane showed good and repeatable responses to temperatures in the range of 283-363 K. The luminescence intensity exhibited high sensitivity to temperature changes, with a relative thermal sensitivity of 7.61% K^-1 in air and 5.41% K^-1 in pure water. In conclusion, the developed membrane demonstrates potential as a promising candidate for use in fluorescence thermometers in both air and water environments.