Room Temperature Synthesis of Phosphine‐Capped Lead Bromide Perovskite Nanocrystals without Coordinating Solvents

Abstract

The room temperature synthesis of perovskite nanocrystals (NCs) is typically achieved by employing a ligand-assisted reprecipitation (LARP) method, which can be handled in air, and its products are comparable to what is obtained using the traditional hot-injection method. However, the LARP method typically requires the use of coordinating polar solvents such as dimethylformamide, that are not appropriate for large-scale production due to toxicity concerns and can also degrade or form defective perovskite NCs. Herein, an amine and oleic acid-free room temperature synthesis of lead bromide perovskite NCs is reported that uses a combination of trioctylphosphine oxide and diisooctylphosphinic acid ligands. This combination of ligands provides a stable platform for the polar-solvent-free synthesis in air of fully inorganic CsPbBr3 (fwhm ≈14 nm, emission = 519 nm) and hybrid organic-inorganic FAPbBr3 (fwhm ≈19 nm) NCs with photoluminescence emission between 530-535 nm which is in line with the Rec. 2020 color standards. In addition, it is shown that compared to a traditionally-used ligand combination, phosphine ligands can be easily removed from the surface of the NCs, which is important for the future development of this technology in optoelectronic devices.

Bandwidth limits of luminescent solar concentrators as detectors in free-space optical communication systems

“…The solution of NCs was then stored in a refrigerator for 24 h. A final centrifugation step was then used to remove the precipitate before it was used for the experiments. The synthesis of Cs-oleate and NCs follows previously published recipes 23 , 41 .…”

Perovskite Nanocrystals: Synthesis, Stability, and Optoelectronic Applications

“…In addition, it was shown that compared with a traditionally used ligand combination, phosphine ligands could be washed off easily, which would benefit the future development of optoelectronic devices. [ 52 ]…”

Lead Halide Perovskite Nanocrystals: Room Temperature Syntheses toward Commercial Viability

“…Typically, short esters have been most successful. Depending on the ligand system employed, butyl acetate, [44] ethyl acetate, [35,41,43,[71][72][73][74][75][76][77] mixtures of ethyl and methyl acetate, [78,79] and methyl acetate alone, [67,[80][81][82][83] have been employed. Figure 6 shows a screening study of 36 potential antisolvents, it concurred on the efficacy of short esters, but indicated that diethylene glycol dimethyl ether (diglyme) was the most effective.…”