Spectral Tuning, Stabilities under External Exposures, and Spontaneous Enhancement of Emission Intensity in Grown‐into‐Glass All‐Inorganic Metal Halide Perovskite Nanocrystals

Abstract

Herein, the grown-into-glass (GIG) CsPbBr 3 :Ln 3+ (Ln = La, Lu) nanocrystals (NCs) are designed and fabrictaed using an in situ nanocrystallization method. It is shown that a substitution of Pb 2+ sites with Ln 3+ ions leads to a blueshift of emission position induced by an increase of the bandgap of CsPbBr 3 . Additionally, the GIG-samples are revealed to feature excellent photoluminescent (PL) properties after being immersed respectively in water for 300 days at room temperature, boiling water for 12 h, and corrosive environments for 24 h, as well as recoverable PL intensity either after several cycles of heat-cooling experiments or after being continuously exposed to a 405 nm laser irradiation. Besides, a spontaneous enhancement of 20-25% of emission intensity during the 1-2.5 hours' stage of a 405 nm laser irradiation, attributed to the radiative recombination of charge carriers that can be de-trapped from trapping levels upon the laser light irradiation and that then spontaneously reinforces the emission intensity, is observed in the GIG-CsPbBr 3 :Ln 3+ NCs. Finally, a white light-emitting prototype, with a CIE chromaticity coordinate at (0.4110, 0.3706), a color rendering index of 89 and a correlated color temperature of 3363 K is realized by combining the GIG-CsPbBr 3 NCs, YAG:Ce and CaWO4:Eu phosphors.

Eu2+:CsCaX3 (X = Cl, Br, I) perovskite nanocrystals in glasses for blue light-emitting applications

“…The dense and inert structures of glasses have been utilized to improve the chemical stabilities of cesium lead halide PNCs embedded inside. 33 Chemical stability of Eu 2+ :CsCaX 3 PNCs in glass is evaluated by recording the change in PL intensity by immersing glass specimens in water at room temperature (Fig. 5(a)).…”

“…These advantages of glasses have been nicely demonstrated by cesium lead halide PNC doped glasses. [32][33][34][35] Consequently, it is expected that stabilities of CsCaX 3 PNCs can also be improved by incorporating these nanocrystals in glass matrices. Since the precipitation of nanocrystals in glasses is strongly affected by the composition and structure of glass, alumino-borate glasses with high concentrations of calcium and halogen are designed.…”

Role of chain length in the physical properties and hydrophobicity of (CnH2n+1NH3)2PbX4 (n = 6, 8, 10, 12, 14, and 16; X = Br and I) 2D metal halide perovskites

“…While the early investigation of the optical properties is quite limited, this important group of publications provides a very accurate and solid structural basis for current research. 4–6,10,11…”

“…While the early investigation of the optical properties is quite limited, this important group of publications provides a very accurate and solid structural basis for current research. [4][5][6]10,11 In particular, Billing reported the crystal structure and phase transition behavior of the (C n H 2n+1 NH 3 ) 2 PbI 4 perovskite series for 4 r n r 16 showing, in general, the presence of multiple reversible phase transitions due to changes in the hydrocarbon chains and the relative arrangement of the inorganic layers. [4][5][6] In general, all these systems undergo two first order phase transitions, with the first one, when n = 6, 8, and 10, between 235 and 275 K, and the second one in the temperature interval from 313 to 340 K. 6 When n is 410, both these phase transitions are above room temperature.…”

Mechanical Control of Polaritonic States in Lead Halide Perovskite Phonons Strongly Coupled in THz Microcavity

“…The strong light–matter interaction leading to an efficient quantum-level system can be provided by phonon polaritons based on multifunctional materials. − In particular, metal halide perovskites have attracted considerable attention owing to their significant physical properties, such as large diffusion length, high absorption coefficient, and high carrier mobility. − The crystallinity of metal halide perovskites is a vital factor for the transport properties in optoelectronic devices, which can be accomplished by a low-cost solution-processed spin-coating method followed by annealing of the films. Owing to their advantageous optical properties, they are considered a novel platform for optoelectronic device applications, such as solar cells, , transistor, , light emitting diodes (LEDs), , and photodetectors. , More recently, metal halide perovskites have emerged as novel materials for THz devices as they have representative phonon modes in the THz frequency region. − Importantly, phonon states in metal halide perovskite materials have been introduced as an excellent platform for polaritonic states that are strongly coupled with the electric fields in metamaterials. , Phonon-polaritons with large Rabi splitting have been observed in highly crystallized films, reaching a strong coupling regime.…”