Fabrication of polystyrene/upconversion nanocrystals nanocomposite spheres through in situ dispersion polymerization

This paper presents a feasible and efficacious procedure to synthesize polystyrene/upconversion nanocrystals (PS/UCNCs) nanocomposite spheres with raspberry-like structure via an in situ dispersion polymerization technique. During this process, polyacrylic acid (PAA) as stabilizer plays the key role in adsorbing UCNCs, including NaYF 4 :Yb 3+ –Er 3+ , NaYF 4 :Yb 3+ –Tm 3+ and NaYF 4 :Yb 3+ –Ho 3+ onto the PS surfaces. TEM and SEM images confirmed the raspberry-like morphology of the obtained nanocomposite spheres. The effect of synthetic conditions, for instances, PAA amount, type and concentration of UCNCs on the structure and fluorescence of the PS/UCNCs nanocomposite spheres were studied in detail.