Phase transformation, morphology control, and luminescence evolution of cesium lead halide nanocrystals in the anion exchange process

Abstract

CsPbX3 NCs with different photoluminescence properties were synthesized by anion exchange. A mechanism was supposed by exploring luminescence evolution.

Fully‐Inorganic Trihalide Perovskite Nanocrystals: A New Research Frontier of Optoelectronic Materials

“…[36] Similarly, the crystal structure of CsPbBr 3 nanowires remains corner-sharing orthorhombic after exchange with I − or Cl − anions, with only a slight shift in the XRD pattern due to lattice expansion or contraction caused by the substitution of the larger I − ion or smaller Cl − ion, respectively ( Figure 2b). [108] This finding is consistent with ref. Nevertheless, Yang's group found that the phase transforms from cubic to orthorhombic by increasing the inserted level of I − anions of CsPbBr 3−x I x NCs.…”

“…[63] CsPbX 3 bulk crystals crystallize as cubic, orthorhombic, and tetragonal polymorphs of the perovskite lattice, which is related to the total system energy and environment temperature. [22,34,36,58,69,77,79,[105][106][107][108] Here, we take CsPbBr 3 NCs as an example to reveal phase identity and phase transformation. More recently, the crystal structure issues of CsPbX 3 NCs with various shapes have been widely investigated.…”

Hybridization of CsPbBr3 Perovskite Nanocrystals with Polymer Nanofiber to Improve their Luminescence Stability

“…The high resolution XPS spectrum of Cs 3d showed two peaks at 738.2 and 724.2 eV, corresponding to the Cs 3d 3/2 and Cs 3d 5/2 levels (Figure c) . An obvious Br 3d signal at a binding energy of 68.1 eV could also be observed (Figure d) . Furthermore, the measured binding energies of Pb 4f, Cs 3d, Br 3d were very similar to those of CsPbBr 3 synthesized by other methods.…”

First-principles study on material properties and stability of inorganic halide perovskite solid solutions CsPb(I1−xBrx)3

“…Halide anion exchange has proven to be a very promising way for producing the cubic CsPbI 3 nanocrystals and even bulk at low temperature, taking advantage of high mobility of halide anions [28,29,30,31,32]. To do this, the cubic CsPbBr 3 nanocrystals were first prepared and then soaked in a PbI 2 or PbCl 2 solution, followed by a fast, partial or complete anion exchange of Br-to-I or Br-to-Cl at low temperature of 40 − 75 • C without change of cubic phase and crystal shape [28,29].…”