Highly Thermotolerant Metal Halide Perovskite Solids

Abstract

By virtue of their narrow emission bands, near‐unity quantum yield, and low fabrication cost, metal halide perovskites hold great promise in numerous aspects of optoelectronic applications, including solid‐state lighting, lasing, and displays. Despite such promise, the poor temperature tolerance and suboptimal quantum yield of the existing metal halide perovskites in their solid state have severely limited their practical applications. Here, a straightforward heterogeneous interfacial method to develop superior thermotolerant and highly emissive solid‐state metal halide perovskites is reported and their use as long‐lasting high‐temperature and high‐input‐power durable solid‐state light‐emitting diodes is illustrated. It is found that the resultant materials can well maintain their superior quantum efficiency after heating at a temperature over 150 °C for up to 22 h. A white light‐emitting diode (w‐LED) constructed from the metal halide perovskite solid exhibits superior temperature sustainable lifetime over 1100 h. The w‐LED also displays a highly durable high‐power‐driving capability, and its working current can go up to 300 mA. It is believed that such highly thermotolerant metal halide perovskites will unleash the possibility of a wide variety of high‐power and high‐temperature solid‐state lighting, lasing, and display devices that have been limited by existing methods.

High Stability and Strong Luminescence CsPbBr3/Cs4PbBr6 Perovskite Nanocomposite: Large‐Scale Synthesis, Reversible Luminescence, and Anti‐Counterfeiting Application

“…This consistent phenomenon can be attributed to the effective passivation effect of the Cs 4 PbBr 6 matrix, which contributes to reduce surface defects of CsPbBr 3 QDs, improve fluorescence intensity, enhance the PLQY and increase the average lifetime. [12][13][14][15][16][17] However, the subsequent decrease is due to the quenching effect of the increased concentration of CsPbBr 3 QDs. The enlarged time-resolved PL decay curves of the nanocomposite samples are shown in Figure S7, Supporting Information, which makes it clearer.…”

“…Further, the characteristic peaks emerged at 2θ = 30.5° and 34.3°, which is in good agreement with the (2 0 0), (2 1 0) planes of the cubic CsPbBr 3 phase (PDF #75-0412). [13,37] To explore the optical behavior of the nanocomposite, the ultraviolet-visible (UV-Vis) absorption, photoluminescence excitation (PLE), and PL spectra were collected. As shown in Figure 2c, the absorption spectrum of the nanocomposite shows one valley shape in the green spectra region (510 nm), while another one is in the UV region (< 350 nm).…”

“…[9][10][11] In short, finding a facile approach to obtain solid CsPbX 3 QDs with high stability and PLQY still requires significant effort.Various strategies have been applied to enhance the structural stability of QDs using the appropriate surface passivation or encapsulate technology. For example, the stabilities of the CsPbBr 3 QDs have been improved by coating them into inert shells (CsBr, [1] Cs 4 PbBr 6 , [12][13][14][15] CdS, [16] and ZnS [17] ), mesoporous materials (silica molecular sieve, [18] mesoporous silica, [19,20] and metal-organic frameworks [21,22] ), inorganic oxides (Al 2 O 3 , [23,24] SiO 2 , [25,26] Al 2 O 3 /SiO 2 , [27] TiO 2 , [28] and ZrO 2 [29] ), and polymer matrixes (polystyrene, [30] polymethyl methacrylate, [31] polyvinylidene fluoride, [32] and thermoplastic polyurethane [33] ). However, these methods require elaborate processes and show the attenuated PLQY.…”

“…Conversely, recent studies prove that the 0-D cousins (Cs 4 PbBr 6 ) of CsPbBr 3 possess high PLQY and good stability, [34,35] which inspires us to design a CsPbBr 3 /Cs 4 PbBr 6 heterostructure. [12][13][14][15] Meanwhile, using the wide-band-gap Cs 4 PbBr 6 matrix to coat the CsPbBr 3 QDs, more carriers can be easily confined to the CsPbBr 3 region, reducing the probability of electron leakage [16] and improving the optical-electrical properties. Finally, room temperature supersaturation method is very efficient in the synthesis of perovskite.In this paper, we propose a facile low-temperature selfassembly strategy to synthesize the CsPbBr 3 /Cs 4 PbBr 6 nanocomposite with a PLQY of 72% and a product yield of 87%.…”

Highly Efficient and Tunable Emission of Lead‐Free Manganese Halides toward White Light‐Emitting Diode and X‐Ray Scintillation Applications

“…Lead halide perovskites as a new class of semiconductor materials have been rapidly advancing the field of optoelectronic devices due to their exceptional optoelectronic properties especially in the field of solar cell. [1][2][3][4][5][6][7][8][9][10][11][12][13] Recently, some lead halide perovskites and their low-dimensional derivatives with excellent optical properties have shown potentials as downconversion phosphors for white light-emitting diodes (WLEDs) [14][15][16][17][18][19][20][21][22] and scintillators for X-ray imaging. [23][24][25][26][27] Due to the earth-abundant elements and low-cost preparation of lead halide perovskites, they as newly emerged promising light emitters may act as a candidate to replace the nonrenewable rareearth containing traditional phosphors and costly inorganic scintillators.…”