Pure green emission self-crystallization CsPbBr 3 quantum dot glass with Ag + doping for stable light-emitting devices

Jiang

et al. 2021

ACS Appl. Nano Mater.

InGaN-based materials and structures have attracted extensive attention in developing green light-emitting diodes (LEDs), but the fabrication of high-performance low-dimensional green LEDs is seriously limited to the sample preparation, device construction, green gap, and efficiency droop. In this work, a kind of green LED composed of p-type InGaN layers and a one-dimensional wired ZnO via Ga incorporation, featuring a green wavelength of 520.0 nm and a linewidth of about 34.0 nm, was designed. The LED characteristics, with respect to the peak wavelengths and linewidths, are almost constant at different input currents, indicating the insensibility to the quantum-confined Stark effect commonly observed in InGaN-based light sources. The color coordinate is really close to pure green (0.170, 0.797) of the Rec. 2020 standard. Significantly, the efficiency droop in the fabricated LED is temperate, suggesting that the recombination of carriers can occur toward the n-ZnO:Ga/p-InGaN interface instead of the p-InGaN region. With an increase in Ga-doping concentration in ZnO:Ga wires, the main EL peaks show a significant red shift from 520 to 584 nm in the green and yellow emission spectrum. This wavelength-tuning is further confirmed by the successfully varied color coordinates. The fabrication of one-dimensional wired green LEDs not only can break through the green gap but also can work as a potential candidate to developing solid-state lighting in the visible band for a wide range of practical applications.

Section: Resultsmentioning

confidence: 68%

Wavelength-Tunable Green Light Sources Based on ZnO:Ga Nanowire/p-InGaN Heterojunctions

Jiang

et al. 2021

ACS Appl. Nano Mater.

“…Therefore, the Cs 4 PbBr 6 QDs were densely grown in the uppermost layers of the whole glass ceramic, which actually is a process of self-crystallization. 23 Of notice, in the process of rapid cooling, the energy barrier for nucleation will be further reduced due to the appearance of defects, and it evidently favors the growth of the Cs 4 PbBr 6 QDs.…”

Section: Resultsmentioning

confidence: 99%

“…When the two gases volatilize from the glass, the free Cs + , Pb 2+ , and Br – in the glass matrix will be carried to the outermost layer of the molten glass, and when the molten glass is cooled rapidly, Cs 4 PbBr 6 crystal nuclei will be first formed on the glass surface. Therefore, the Cs 4 PbBr 6 QDs were densely grown in the uppermost layers of the whole glass ceramic, which actually is a process of self-crystallization . Of notice, in the process of rapid cooling, the energy barrier for nucleation will be further reduced due to the appearance of defects, and it evidently favors the growth of the Cs 4 PbBr 6 QDs.…”

Section: Resultsmentioning

confidence: 99%

Origin of Radioluminescence in Low-Dimensional Halide Perovskite Glass Ceramics under X-ray Excitation

et al. 2021

J. Phys. Chem. C

Self Cite

Zero-dimensional halide perovskite materials have recently shown great potential in the field of X-ray detection. Herein, Cs4PbBr6 quantum dots (QDs) glass ceramics, which can be used as scintillator materials, were fabricated by a molten salt method. The perovskite glass ceramics not only maintained the original high air stability of glass but also had high quantum yield (49.7%) and crystallinity. Not only that, QD-based solid powder exhibited strong green luminescence under the illumination of both X-ray and UV light. In addition, a novel dual emission is observed in the radioluminescence spectra of Cs4PbBr6 QDs. Electron paramagnetic resonance (EPR) and X-ray diffraction (XRD) suggested that the novel dual emission is associated with the Br vacancy. It is worth noting that after repeated X-ray irradiation, the radioluminescence (RL) intensity of the Cs4PbBr6 QDs glass ceramic sample can be increased to 6.2 times the initial intensity, which provides a new idea for the long-term repeated use of scintillator materials. These results demonstrated that Cs4PbBr6 QDs glass ceramics are promising materials in scintillator fields.

“…9 So far, CsPbX 3 perovskite QDs have been successfully precipitated in various glass matrices, such as borosilicate, [10][11][12] phosphosilicate, 13 tellurite glasses. 14,15 Recently, Zhang et al reported that red light-emitting CsPbI 3 and CsPbCl 3 QDs could be simultaneously precipitated in the glass. Due to the effective reabsorption, CsPbCl 3 :CsPbI 3 hybrid nanocrystals (NCs) show higher PLQY and higher PL intensity than pure CsPbI 3 NCs.…”

Section: Introductionmentioning

confidence: 99%

“…For instance, Liu et al first reported that all inorganic CsPbBr 3 QDs could be precipitated in phosphate glasses by annealing 9 . So far, CsPbX 3 perovskite QDs have been successfully precipitated in various glass matrices, such as borosilicate, 10–12 phosphosilicate, 13 tellurite glasses 14,15 . Recently, Zhang et al.…”

Section: Introductionmentioning

confidence: 99%

Effect of ZnO on the crystallization and photoluminescence of CsPbI₃ perovskite quantum dots in borosilicate glasses

Chen

Xia

et al. 2022

J Am Ceram Soc

CsPbI 3 perovskite quantum dots (QDs) doped borosilicate glass was prepared by the process of melt-quenching and subsequent annealing. With the introduction of ZnO to the parent glass as the glass network intermediate, the optical properties of the resultant samples are dramatically enhanced. Both the photoluminescence (PL) intensity and photoluminescence quantum yield (PLQY) shows a strong dependence on ZnO concentration as ZnO is found to facilitate the precipitated of the QDs by reducing the connectivity of three-dimensional glass network built from SiO 4 tetrahedrons. The tunable visible-band PL emission of the CsPbI 3 QD-doped glass could find potential applications in white LEDs and lasers.