Synergistic role of ZnO and coordination polymers in enhancing the O2 sensitivity of [Ru(bpy)3]2+

Abstract Optical oxygen sensors based on luminescence quenching are highly suitable for non-invasive and real-time gas detection owing to their high sensitivity, fast response, and operational simplicity. In this study, an optical oxygen gas sensor was developed using the [Ru(bpy) 3 ] 2+ complex incorporated into thin film matrices comprising ZnO and two distinct coordination polymers: PKY210 [Co(µ 3 -dmg)(µ-dpetan)] n (1) and PKY221 [Ni 2 (µ-dmg) 2 (H 2 O) 2 (µ-dpetan) 2 ] n (2). The objective was to enhance the oxygen-sensing performance of the Ru-based luminescent dye by leveraging the high surface area of ZnO nanoparticles along with the porosity and host–guest interactions provided by the coordination polymers. Photoluminescence quenching experiments performed under varying oxygen concentrations (0–100% O 2 ) revealed that all modified films exhibited dynamic quenching behavior, with significant improvements in sensitivity compared to the dye-only system. Among the investigated systems, the Ru(bpy) 3 2+ _PKY210_ZnO film demonstrated the most effective oxygen response, showing the highest Stern–Volmer constant ( K sv = 2.71 × 10 −2 ) and intensity ratio ( I 0 / I 100 = 4.02). These findings highlight the synergistic role of ZnO and the coordination polymer networks in facilitating oxygen diffusion and strengthening dye–matrix interactions. This strategy offers a promising pathway for the development of high-performance optical oxygen sensors.