Luminophore self-quenching and microenvironment heterogeneity in polymer–ceramic pressure-sensitive paints

Polymer–ceramic pressure-sensitive paints (PC-PSPs) enable time-resolved pressure-field measurements with high spatial resolution. Their porous binder, formed by a large proportion of ceramic particles and a small amount of polymer, facilitates oxygen diffusion, ensuring a rapid response. However, the low polymer concentration in PC-PSPs leads to severe dynamic self-quenching of luminescence, which is further complicated by the microenvironment heterogeneity induced by the high concentration of ceramic particles. While these factors significantly deteriorate the static sensing performance of PC-PSPs, the underlying mechanisms remain poorly understood. To address this gap, this paper introduces a photophysical model for the quenching mechanism in PC-PSPs, considering the dynamic self-quenching effect and microenvironment heterogeneity. The proposed model is verified based on experimental results of PC-PSPs with varying polymer-to-ceramic particle ratios. The effects of dynamic self-quenching and microenvironment heterogeneity on pressure sensitivity, response time, and photodegradation are analyzed based on theoretical analysis and experimental results. The findings can provide valuable reference for the design and optimization of PC-PSPs.