Reprecipitation induced isolation of ligand-free Cs4PbBr6 nanodisks as a green emissive UV light filter

Abstract

A strong green emissive UV shielding polymer film has been prepared by incorporating different weight fraction of ligand-free Cs4PbBr6 nanodisks into a polymer matrix. A routine reprecipitation method is introduced to isolate ligand-free Cs4PbBr6 nanodisks for better dispersion in a polymer matrix. As-prepared polymer film shows an excellent UV shielding with increasing content of ligand-free Cs4PbBr6 nanodisks. About 30% of UV shielding was observed with 7.5 mg of ligand-free Cs4PbBr6 nanodisks, while the maximum UV shielding of 80 and 83% was witnessed in a polymer film containing 25 mg of ligand-free Cs4PbBr6 nanodisks under a UV lamp and direct daylight sources, respectively. The UV-shielding capability of polymer film was further verified by testing of UV light induced rhodamine B degradation and compared to pure polymer film. Furthermore, due to a down-conversion of ligand-free Cs4PbBr6 nanodisks, a strong green emission was observed of converting high energy UV radiation into green emission, upon illumination of UV light. Thus, the development of green emissive UV shielding polymer film can be recommended to use as a packaging film, emulsion, paints and protective coating etc.