Binuclear charged copper(I) complex as a multimode luminescence thermal sensor

Luminescence thermometry became one of the most rapidly developing scientific areas in the last decade. A lot of scientific groups are working on the design of a highly sensitive and accurate thermometer based on monitoring the chosen luminescence parameter. However, it is still a challenge to create a multimode sensor utilizing several temperature-dependent parameters for thermometry, which could broaden the working range and improve thermometric characteristics. Here, we successfully demonstrate the binuclear helical charged complex [L3Cu2](BF4)2 (L = 1-pyridine-2-ylphospholane) in head-to-head configuration with solid-state single-band emission as a multimode optical thermometer. Thermal sensing was provided using luminescence intensity ratio, spectral line position, bandwidth, and lifetime. Ratiometric temperature determination was performed by the successful use of deconvolution analysis. The thermometric performance was studied in terms of relative thermal sensitivity, which was varied from 0.93 % K−1 for line position to 0.11 % K−1 for bandwidth at 298 K. The obtained results show Cu(I) complex as a cheap multimode luminescence thermal sensor in the 98–393 K range.