Gold nanoparticles-mediated nanosecond laser-induced polystyrene carbonization with highly luminescent amorphous products

A highly soluble Au(I) gold precursor is used to produce a nanocomposite material consisting of a polystyrene matrix and gold nanoparticles. Irradiation of such a material with nanosecond laser pulses at the plasmon resonance wavelength leads to the formation of highly luminescent black spots containing amorphous carbon, as confirmed by HR TEM analysis. A simple model, based on laser heating of a nanoparticle to a temperature of more than 2000 K and stabilization of this temperature by the endothermic process of polystyrene carbonization, fits well the dependence of the luminescent signal increment on the laser fluence.