Rapid synthesis and theoretical analysis of CH3NH3Pb1-xCdxBr3 perovskite quantum dots for backlight LEDs: A step towards enhanced stability

Abstract

Colloidal CH 3 NH 3 Pb 1-x Cd x Br 3 perovskite quantum dots (PQDs) have shown potential for the development of new solar cell and light-emitting diodes due to their enhanced optoelectronic properties. Here, we have reported a potential ligand-assisted room temperature rapid synthesis method for partial cation exchange in colloidal CH 3 NH 3 Pb 1-x Cd x Br 3 PQDs, where exchange of Pb 2+ takes place for various similar cations, which result in doped CH 3 NH 3 Pb 1-x Cd x Br 3 maintaining its original PQDs shape and structure. There was lattice contraction was observed into the Cd doped perovskite. A blue shift in optical spectra was observed due to partial Pb 2+ exchange in place of Cd 2+ , however high photoluminescence quantum yields, sharp absorption features, and narrow emission of the original CH 3 NH 3 Pb 1-x Cd x Br 3 PQDs remained the nearly same. XPS study confirmed the incorporation of Cd 2+ ions in the place of Pb 2+ . Theoretical analysis was also performed to study the different structural and optical aspects of the doped perovskite samples. Furthermore, a prototype perovskite QDs based white LEDs was fabricated that have a higher color gamut. The current work presents a new possibility to develop stable PQDs with enhancing optoelectronic properties. • Rapid perovskite quantum dot synthesis within 30 min. • Cd incorporation enhanced the stability and performance of PQDs. • Theoretical and experimental investigation of Cd: MAPbBr 3 PQDs. • High color purity, PLQY, and intense PQDs enhanced thin films. • Backlight LEDs with high color gamut.