Stabilization of CsPbBr₃quantum dots for photocatalysis, imaging and optical sensing in water and biological medium: a review

Abstract

Of all the quantum dots CsPbBr3 perovskite quantum dots (CPQDs) have been extensively studied for sensing and photocatalysis because of their desired photophysical properties such as, optical absorption, high quantum...

Origin of the near 400 nm Absorption and Emission Band in the Synthesis of Cesium Lead Bromide Nanostructures: Metal Halide Molecular Clusters Rather Than Perovskite Magic-Sized Clusters

“…The 426 nm absorption and 435 nm emission bands can be attributed to CsPbBr 3 PMSCs, [14][15][16][17]21,24,25,31 while the 487 nm emission band is most likely due to a small amount of CsPbBr 3 PQDs with a high photoluminescence quantum yield (PLQY) or trap states in the structure. 3,8,10,12,18,36 Figure 2C shows the UV−vis absorption and PL emission spectra of CsPbBr 3 nanoparticles passivated with MAA and BZA. These MAA + BZA perovskite nanoparticles have two distinct excitonic peaks at 393 and 415 nm but several emission peaks at 399, 422, 443, 488, and 519 nm.…”

“…The 422 and 443 nm e m i s s i o n p e a k s a r e a t t r i b u t e d t o C s P b B r 3 PMSCs 14−17,21,24,25,31 and the 488 nm and 494 nm emissions to CsPbBr 3 PQDs. 3,8,10,12,18,36 Figure 3A shows the UV−vis absorption and PL emission spectra of CsPbBr 3 nanoparticles passivated with VA and BTYA. This condition also renders two electronic absorption bands at 404 and 430 nm and multiple PL emission bands at 409, 433, and 461 nm.…”

“…13,17,27,29 As before, the overlapping absorption and emission bands of the approximate 400 nm peaks regardless of the presence of Cs + suggest that PbBr 2 MCs are responsible for the 404 nm absorption band and 409 nm emission band observed in Figure 3A PMSCs, [14][15][16][17]21,24,25,31 and the 461 nm emission peak is from small CsPbBr 3 PQDs or trap states. 3,8,10,12,18,36 Figure 3C shows the UV−vis absorption and PL emission spectra of CsPbBr3 nanoparticles passivated with VA and BZA. These nanoparticles are represented by one broad electronic peak at 393 nm, and two emission bands at 403 and 501 nm.…”

“…13,17,27,29 The 501 nm emission band is most likely attributed to CsPbBr 3 PQDs with a high PLQY, which may contribute to the low intensity of the PbBr 2 MCs. 3,8,10,12,18,36 Figure 4A depicts the UV−vis absorption and PL emission spectra of CsPbBr 3 nanoparticles passivated with OcA and BTYA. These nanoparticles are characterized by a single strong absorption band at 404 nm and a broader absorption band at 434 nm, as well as several emission peaks at 410, 436, 462, and 528 nm.…”

“…[14][15][16][17]21,24,25,31 The 462 nm emission band is from small CsPbBr 3 PQDs or trap states, and the 528 nm emission band is from CsPbBr 3 PQDs. 3,8,10,12,18,36 The UV−vis absorption and PL emission spectra for CsPbBr 3 nanoparticles passivated with OcA and BZA are shown in Figure 4C. The product has three excitonic species at 390, 421, and 456 nm, and two emissive species at 404 and 504 nm.…”