Improving the stability and optical properties of CsPbI3 perovskite nanocrystals by 1-Octadecanethiol through surface modification

Understanding and minimizing non-radiative recombination losses in perovskite light-emitting diodes

“…According to a recent study, defects caused in purification process can be avoided by increasing the coordination ability between the Pb 2+ and the thiol group of ligands, resulting in nanocrystals with a PLQY of 98%. 144 In high affinity system, the post treatment with octyl-ammonium sulfate can produce a CsPbX 3 /PbSO 4 core/shell heterostructure, which can improve the radiative recombination and exhibit excellent optical properties. 145 Etching the surface selectively represents a promising pathway for mitigating the optical defects in perovskite nanocrystals.…”

Cu-Doping Induced Phase Transformation in CsPbI3 Nanocrystals with Enhanced Structural Stability and Photoluminescence Quantum Yield

“…Introduction of Cu atoms in an alloy of double perovskites containing Ag and Na has been found to increase the density and radiative recombination rates of self-trapped excitons along with the improved thermal stability of crystals. 30 However, it is also known that doping can induce phase changes by degrading the quality of perovskites, 14 which is a challenging issue.…”

“…However, it undergoes a phase transformation at low temperatures, thus degrading its properties. This stability can be increased in various ways such as by modification of the surface, , by decreasing the dimensionality of the perovskite nanostructures, − and by inorganic oxide or polymer encapsulation, , but these methods have their limitations too. Surface modification by attaching ligands can decrease the mobility of free charge carriers and hence limits its use in device applications.…”

Thermal tolerance of perovskite quantum dots dependent on A-site cation and surface ligand

“…Hence, regardless of FA-rich and Cs-rich PQDs, the thermal stability of these PQDs is firmly associated with their ligand bindings. Many recent studies demonstrate that the strong bonding between PQDs and the functional surface ligands such as 2,2-iminodibenzoic acid 38 , hexamethyldisilathiane 39 , trioctylphosphine 40 , 1-octadecanethiol 41 , 1-propyl-3-methylimidazolium iodide 42 , 2-naphthalenesulfonic acid 43 , sulfur−oleylamine 44 , etc., is beneficial in protecting the phase stability of the PQDs. Particularly, Dutta et al show that the introduction of separately mixed oleylamine and hydroiodic acid (OLA-HI) can lead to a substantial stabilization of CsPbI 3 PQDs at 260 °C (100 °C higher than the usual synthesis temperature) via enhancing the binding of oleylammonium ions on QD surface 45 .…”