Low-Dimensional CsPbBr3@CoBr2 Super-Nanowire Structure for Perovskite/PMMA Composite with Highly Blue Emissive Performance

Abstract

In this study, low-dimensional CsPbBr3@CoBr2 super-nanowire (SNW) structures were synthesized via a one-pot heating strategy for highly blue emissions. By introducing CoBr2 to CsPbBr3 precursors, the shape of perovskite nanocrystals was changed from cuboids to a super-nanowire structure, as revealed through a transmission electron microscope. SNWs were formed from stacked segments of nano-plates (lateral dimension of 10–12 nm and thickness of ~2.5 nm) with lengths of several microns. The fabricated sample absorbs light at a wavelength of <450 nm, and it is emitted at a wavelength of 475 nm. It also has a radiant flux conversion efficiency of up to 85% when stimulated by a 430 nm LED light source. The average decay time of up to 80 µs indicates that they effectively prevent the recombination of electron–hole pair. The optical performance still remains over 65% when the ambient temperature is up to 120 °C compared with that under room temperature. The excellent color purity, optical quantum efficiency, long carrier lifetime, and thermal stability make CsPbBr3@CoBr2 SNWs highly promising for a range of photolumicescence applications, such as a high color rendering index lighting and transparent blue emissive screen.