Photoluminescence quenching of conjugated polymer nanocomposites for gamma ray detection.

The high atomic number of bismuth iodide and the high-sensitivity photoluminescence quenching of conjugated polymers are leveraged in their nanocomposites for the detection of high-energy photons. With the introduction of oleylamine, the composites can be processed from solutions in organic solvent into high-quality films containing as much as 50 wt% BiI(3). BiI(3) in the resulting ternary composites is dispersed on a nanoscale or smaller, allowing the formation of transparent composites. Oleylamine was found to form an interfacial layer between the polymer matrix and BiI(3) nanodomains to block charge transfer between BiI(3) and the polymer. Upon gamma ray exposure, the luminescent intensity of the ternary composites decreased linearly with the radiation dosage.