Pursuing Reliability and Sensitivity of Pr³⁺ Fluorescence Temperature Sensing: Through the Lens of Excitation Strategy

Abstract Despite the remarkable luminescent properties and temperature sensing capabilities of lanthanide materials, their photothermal effect in practical temperature measurement systems presents a major challenge to sensing reliability. Herein, taking Pr 3+ as a typical exemplar, the influence of excitation wavelength and excitation approach on temperature sensing is systematically examined. The pulsed laser excitation method is identified as an efficient tactic to restrain the self‐heating of luminescence materials. In accordance with this principle, it is discovered that diverse excitation wavelengths give rise to alterations in the internal energy transport channels and further impact the temperature sensing performance. The 980 nm pulsed laser can result in the non‐thermal coupling occupying states of 3 P 0 / 3 P 1 , which are recognized as thermal coupling energy levels in the conventional concept, and yield a relative sensitivity ( S r ) performance more than three times superior to that of down‐shifting‐based sensing. The work provides a comprehensive analytical solution for achieving highly sensitive and stable temperature sensing based on excitation wavelength and working mode strategies.