Luminescent Tb(III) and Sm(III) complexes with a 1,4,7-triazacyclononane-based tris-aryloxide ligand for high-performance oxygen sensors

Taking advantage of the outstanding oxygen-sensitive luminescence properties of the previously synthesised Tb(iii) complex [{(^MeMeArO)₃tacn}Ln^III(THF)] (1^Tb, Ln = Tb), herein, we have prepared an oxygen sensor based on 1^Tb embedded in polystyrene film (1^Tb/PS) and found that 1^Tb/PS shows the highest sensitivity (I₀/I₁₀₀ = 14.9) and the fastest response (response/recovery time = 1.9 s/2.9 s), among the lanthanide(iii)-based oxygen sensors with f-f emission. Moreover, we have prepared the lanthanide(iii)-based colorimetric luminescent oxygen sensor (1^TbSm/PS) with green-yellow-red responses, by using 1^Tb and a newly synthesised oxygen-insensitive Sm(iii) complex (1^Sm, Ln = Sm; Φ = 0.010 and τ = 12.2 μs).