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

We report a novel ytterbium complex [Yb(tta)3DFQZ] which exhibited obviously enhanced two-photon sensitized near-infrared luminescence properties of Yb(3+) compared to the usually reported Yb(3+) 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 Yb(3+) 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 Yb(3+) 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.