An ytterbium complex with unique luminescence properties: detecting the temperature based on a luminescence spectrum without the interference of oxygen

Abstract

We report a novel ytterbium complex [Yb(tta)₃DFQZ] which exhibited obviously enhanced two-photon sensitized near-infrared luminescence properties of Yb³⁺ compared to the usually reported Yb³⁺ complexes, with a two-photon excitation action cross-section of 22 GM under excitation at 860 nm at 298 K. Unlike other lanthanide complexes, [Yb(tta)₃DFQZ] under nitrogen exhibited quantum yields for the sensitized Yb³⁺ luminescence that increased with increasing temperature. [Yb(tta)₃DFQZ] was dispersed in a polymer film to prepare a near-infrared-emission sensor that made it possible to conveniently detect the temperature in a range from 178 to 378 K without the influence of O₂, via a luminescence spectrum of Yb³⁺ in the film. This provided a promising solution to the long-standing problem that complex calculations and complicated structures are usually needed for eliminating the influence of O₂ on temperature sensing with a luminescent sensor.