Suitable selection of high-energy state excitation to enhance the thermal stability of Eu³⁺ and the sensitivity of La₂CaSnO₆:Eu³⁺,Mn⁴⁺ temperature measuring materials

Luminescence thermal quenching in luminescent materials has posed a perplexing challenge. This study has elucidated an innovative approach for enhancing the thermal stability of Eu3+ ion doped materials. The synthesis of La2CaSnO6:Eu3+ materials was undertaken to investigate this phenomenon, revealing a noteworthy finding that the thermal stability of Eu3+ ions exhibited a remarkable improvement when excited at a specific wavelength corresponding to the H-5(3) energy level, surpassing the performance observed at other excitation wavelengths. Building upon this significant observation, the development of a La2CaSnO6:Eu3+,Mn4+ temperature probe was pursued. Interestingly, reverse thermal quenching of Eu3+ ion luminescence was observed upon adjusting the excitation wavelength to 318 nm. Under these optimized conditions, the La2CaSnO6:Eu3+,Mn4+ temperature probe achieved a maximum absolute sensitivity of 0.08523 K-1 along with a relative sensitivity of 2.954% K-1. These compelling results highlight the potential of the approach to enhance the thermal stability of Eu3+ ion doped materials and position La2CaSnO6:Eu3+,Mn4+ as a promising candidate for non-contact temperature sensing applications. In conclusion, this finding suggests that carefully selecting a suitable excitation wavelength corresponding to a high-energy state can significantly facilitate the utilization of Eu3+ ions in luminescence, temperature sensing, and other related fields.