Synthesis of cesium lead bromide nanoparticles by the ultrasonic bath method: A polar-solvent-free approach at room temperature

Govind B Nair; R Krishnan; Arno Janse van Vuuren; H C Swart

doi:10.1039/d2dt03689d

Synthesis of cesium lead bromide nanoparticles by the ultrasonic bath method: A polar-solvent-free approach at room temperature

Dalton Trans. 2022 Dec 20;52(1):70-80. doi: 10.1039/d2dt03689d.

Authors

Govind B Nair¹, R Krishnan^{1

2}, Arno Janse van Vuuren³, H C Swart¹

Affiliations

¹ Department of Physics, University of the Free State, P. O. Box 339, Bloemfontein 9300, South Africa. govind1291@yahoo.com.
² Extreme Light Infrastructure-Nuclear Physics (ELI-NP), 'Horia Hulubei' National R&D Institute for Physics and Nuclear Engineering (IFIN-HH), 077125 Măgurele, Ilfov, Romania.
³ Centre for HRTEM, Nelson Mandela University, Port Elizabeth, 6001, South Africa.

PMID: 36458482
DOI: 10.1039/d2dt03689d

Abstract

Colloidal synthesis of CsPbBr₃ nanoparticles (NPs) is often carried out by involving polar solvents that threaten the chemical stability of the NPs. Here, we report a polar-solvent-free synthesis of all-inorganic CsPbBr₃ NPs by employing an ultrasonic bath approach. The phase evolution of the CsPbBr₃ NPs strongly depended on the duration of ultrasonication. A secondary phase of Cs₄PbBr₆ was also found to evolve, which emitted narrow blue-emission bands. For the longest period of ultrasonication (12 h), the CsPbBr₃ and Cs₄PbBr₆ phases co-existed to produce blue and green emission bands with a photoluminescence quantum yield (PLQY) of 53%. The purest form of CsPbBr₃ phases was observed for the NPs produced by sonicating the precursors for 8 h. They exhibited narrow green emission bands with a PLQY of 50%. The power-conversion efficiency of a silicon solar cell was remarkably increased when coated with the CsPbBr₃ NPs, thus, proving its potential to be used as a spectral downshifter for Si solar cells.