Metal-Enhanced Luminescence of Core-Shell Au@ Resorcinol-Formaldehyde Resin Nanospheres for Oxygen Sensing

Luminescence-based detection has attracted widespread interests in oxygen measurement applications due to its great versatility, simplicity, sensitivity and non-invasive measurement. However, the relatively low quantum efficiency prompts a need for developing methods for luminescent enhancement. Plasmonic nanoparticles are known to efficiently enhance emission of the surrounding dyes with a precise inter-distance of nanoparticles and dyes. Here, we reported a novel plasmon-enhanced luminescence system in which the distance between luminescence dyes (PtTFPP) and metal nanoparticles (Au nanospheres, AuNSs) can be tuned by an organic spacer of Resorcinol-Formaldehyde (RF) to investigate the separation dependence on the emission enhancement in the optical oxygen sensors. A maximum enhancement of up to 6.24-fold has been achieved with a 5 nm thick spacer in the PtTFPP-based oxygen sensors. These findings provide a unique platform for exploring the application of metal-enhanced luminescence (MEL) in luminescence-based measurement for oxygen concentration.