Ultrasonic synthesis of Mn-doped CsPbCl3 quantum dots (QDs) with enhanced photoluminescence

Abstract

Mn-doped CsPbCl3 (CsPbCl3:Mn) perovskite colloidal quantum dots (QDs) attract a great deal of interests, and have great potentials for various optoelectronics applications due to their outstanding optical and electrical properties. However, practical applications of CsPbCl3:Mn QDs are severely limited by the cumbersome preparation methods and low photoluminescence quantum efficiency (PLQY). Herein, we propose a single-step ultrasonic synthesis method to successfully synthesize CsPbCl3:Mn QDs with controlled size and morphology by changing the Mn:Pb ratio. Simultaneously, we introduce triethylamine (TETN) to passivate the surface of CsPbCl3:Mn QDs. The phase purity, microstructure, chemical composition and photoluminescence properties of the samples were investigated by means of various analytic techniques. The synthesized QDs exhibit dual emissions of 411 and 601 nm, ascribing to the excitonic emission of QDs and the characteristic Mn2+ emission, respectively. The quantum yield of the CsPbCl3:Mn QDs could therefore be significantly improved from 17.49 to 41.15%. We believe that the facial synthesis method and the surface passivation of TETN can also be applied to other transition metal or lanthanide ions doped lead halide perovskite QDs.