Improving the Stability of Ball-Milled Lead Halide Perovskites via Ethanol/Water-Induced Phase Transition

Abstract

Recently, lead halide perovskite nanocrystals have been considered as potential light-emitting materials because of their narrow full width at half-maximum (FWHM) and high photoluminescence quantum yield (PLQY). In addition, they have various emission spectra because the bandgap can be easily tuned by changing the size of the nanocrystals and their chemical composition. However, these perovskite materials have poor long-term stability due to their sensitivity to moisture. Thus far, various approaches have been attempted to enhance the stability of the perovskite nanocrystals. However, the required level of stability in the mass production process of perovskite nanocrystals under ambient conditions has not been secured. In this work, we developed a facile two-step ball-milling and ethanol/water-induced phase transition method to synthesize stable CsPbBr3 perovskite materials. We obtained pure CsPbBr3 perovskite solutions with stability retention of 86% for 30 days under ambient conditions. Our materials show a high PLQY of 35% in solid films, and excellent thermal stability up to 80 °C. We believe that our new synthetic method could be applicable for the mass production of light-emitting perovskite materials.

All-inorganic lead halide perovskites for photocatalysis: a review

“…However, mechanical grinding will result in surface flaws and diminish the photocatalytic effectiveness. Kim et al created a simple two-step ball milling approach to create stable CsPbBr 3 132 and discovered that these materials were more stable after 30 days than those that were thermally synthesized under the same circumstances.…”

Electron beam pumping improves the conversion efficiency of low-frequency photons radiated by perovskite quantum dots

“…According to the publication, CsPbBr 3 solutions were synthesized. [27] By using cesium oleate and lead bromide as precursors, CsPbBr 3 quantum dots were produced in an oil phase shielded by an inert gas via thermal injection and rapid ion exchange. After centrifugation and purification by highspeed centrifugation, CsPbBr 3 quantum dot solutions containing only inorganic metals were prepared with hexane as the solvent and a concentration of 10 mg/mL emitting green light.…”