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By increasing the heat treatment temperature, the average size of CsPbBr3 quantum dots (QDs) in the glass matrix was increased, which contributed to a 5.5 fold increase of the optical gain coefficients. And the corresponding lasing threshold decreased from 0.752 mJ cm−2 to 0.138 mJ cm−2. [ABSTRACT FROM AUTHOR]

In this report, a mixed‐metal cation‐based halide perovskite (HP) CsPb1−xTixBr3 quantum dots (QDs) were first embedded in the B–Si–Zn glasses using a traditional approach of melt quenching and heat treating. A battery of test results such as photoluminescence, X‐ray diffraction, and time‐resolved attenuation prove that Ti ions do not destroy the properties of CsPbBr3, and they are successfully doped into CsPbBr3. At the same time, the doping of Ti ions also reduces the toxicity of lead. By altering the ratio of Pb/Ti, we determined the optimum ratio of CsPb0.7Ti0.3Br3 QDs through experimental data. Due to the excellent optical properties and stability of CsPb0.7Ti0.3Br3 QDs glass, it was designed to construct the white‐light emitting diode device with tunable color coordinate, color rendering index, correlated color temperature, and a high luminous efficiency compared with CsPbBr3 QDs glass, which may be a promising candidate for the field of lighting and displays. [ABSTRACT FROM AUTHOR]

CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) represent bright and tunable photoluminescence, it is regrettable that the air instability and poor water resistant properties prevent their application in optoelectronic devices. At the same time, the toxicity of lead is also a major factor restricting its development. As a consequence, we demonstrate the partial replacement of Pb with Mn through conventional melt‐quenching and heat‐treatment method preparation of Mn‐doped CsPb(Cl/Br)3 QD glass. Mn‐doped CsPb(Cl/Br)3 QD glass exhibits high luminescent intensity like QDs. It is important that Mn‐doped CsPb(Cl/Br)3 QD glass with Dual‐Color maintained the same lattice structure like Mn‐doped CsPb(Cl/Br)3 QDs, and highly homogeneous spectral characteristics of Mn luminescence. The intensity and position of this Mn‐related emission are also tunable by altering the experimental parameters, such as the Pb‐to‐Mn feed ratio, annealing temperature. More importantly, the as‐prepared orange Mn‐doped CsPb(Cl/Br)3 QD glass was employed to fabricate white LEDs combined with a commercial Ce3+:Y3Al5O12 phosphor‐in‐glass (Ce‐PiG) on top of a InGaN blue chip. And the constructed WLEDs generate a warm white with an optimal luminous efficacy (LE) of 67.00 lm/W, a high CRI of 81.4, and a low CCT of 4902 K. [ABSTRACT FROM AUTHOR]

Abstract: CsPbBr1.5I1.5 quantum dots (QDs) glasses are synthesized by traditional melting and thermal treated method, CsPbBr1.5I1.5 QDs glasses show vast potential as red fluorescence component in warm WLED applications due to their moderate emission wavelength as well as good opacity property. However, the quantum yield of QDs glasses is still low, therefore, Eu3+ ions is chosen to introduce into CsPbBr1.5I1.5 QDs, the quantum yield is enhanced to 64.7%. After a sequence of testing operations, we find that 6.5%CsPbBr1.5I1.5:0.28%Eu3+ QDs glasses is a strong competitor among red fluorescence solid materials. [ABSTRACT FROM AUTHOR]

Various luminescent carbon materials are artificially synthesized and as admirable fluorescent materials because of the increased research of carbon nanodots (CDs). Herein, a novel solvent-dependent red CDs (rCDs) is introduced through solvothermal method. The as-prepared rCDs remain benzene structure and possess abundant surface function groups that endow them well solubility in various solvents. Furthermore, multicolor luminescence are observed when rCDs are dissolved in different solvents, and the emission wavelength of these materials can be well-tuned from 475 to 624 nm, which presents intensity solvent-dependent properties. Red luminescence carbon phosphors are successfully synthesized by mix rCDs with silica powder. Finally, warm white light emitting diodes (WLEDs) are constructed using rCDs powder with Ce3+: YAG single crystal and blue GaN chips. The results demonstrate that the rCDs can act as red component to modify the correlated color temperature (CCT) and the color rendering index (CRI) of WLEDs. [ABSTRACT FROM AUTHOR]

We report the synthesis of CsPbBr3 QDs with great stability and high quantum yield in phospho-silicate glass, which was fabricated by using a heat-treatment approach, for white light emitting devices. QD glasses exhibited excellent photo- and thermal stability, and significantly prolonged the lifetime of light emitters under ambient air conditions. [ABSTRACT FROM AUTHOR]

The spherical shape copper oxide (CuO) quantum dots (QDs) were successfully fabricated via copper basic calcium sodium borosilicate (NaO-CaO-BO-SiO) precursor obtained with a facile sol-gel technique. The microstructural analysis of doped QDs are systemically characterized, such as transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and X-ray photo-electron spectroscopy. And the results reveal that the CuO QDs with the small size are well dispersed doped in sodium calcium borosilicate glass. Remarkably, the CuO glass materials exhibit the good third-order optical nonlinear susceptibility χ (1.379 × 10 esu), which was investigated by femto-second Z-scan technique at the wavelength of 1550 nm, pulse duration of 50 fs, repetition rate of 50 MHz. The glass hybrids displayed a reverse saturable absorption and self-focusing refraction performance. And the mechanism to explain the third-order nonlinearity of CuO glass may be predominantly originated from the surface plasmon resonance effect, the quantum confinement effect and partly from the thermal effect. Besides, it is interesting that the glass hybrids have significant nonlinear absorption effects that endow the material to the potential value of the application of optical limiting device. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite quantum dots (PQDs) are widely applied in photoelectronics because of their high luminous efficiency. However, PQDs have poor stability, which hinders their practical applications. In this study, controllable crystallization of PQDs is achieved by adding Al2O3 to alter the glass network. Next, Na2CO3 (aq) washing‐heating treatment is used to improve the protective mechanism. Owing to this dual strategy, the prepared CsPbBr3@glass exhibits a high photoluminescence quantum yield (PLQY > 95%) and excellent stability. In a 1000 h accelerated aging experiment, the luminous intensity remains above 96% of the initial intensity. The luminescence intensity shows almost no change after soaking in water for 20 weeks. Finally, the CsPbBr3@CsPbBr1I2@PET light‐conversion film is prepared by the sandwich method. Its color gamut covers 138% of the NTSC 1953 and 102% of the Rec. 2020. This CsPbBr3@glass with a high PLQY and ultrastability will broaden the scope of perovskite materials in displays. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots can form various forms such as nanowires, nanorods, and nanosheets through self‐assembly. Nanoscale self‐assembly can be used to fabricate materials with excellent device properties. This study introduces AuBr3 into CsPb(Br/I)3 quantum dots, causing them to assemble into nanowires. The nanowires form because part of Au3+ is surface‐doped to replace Pb2+, and the [PbX6]4− octahedral structure is distorted. The symmetry of the structural surface is broken, and a dipole‐moment‐induced field is generated, thus promoting self‐assembly. Moreover, the presence of Au nanoparticles (NPs) causes a localized surface plasmon resonance and generates strong van der Waals forces that promote self‐assembly. Finally, to test other applications of perovskite nanowires, the solution method is used to prepare films by compounding the sample solution and polystyrene (PS) for backlighted displays. [ABSTRACT FROM AUTHOR]

All-inorganic lead halide quantum dots (QDs) have attracted immense interest because of their excellent photoelectric properties. By virtue of a similar ionic radius and the same valence state, Rb+/Cs+ mixed-cation have become a novel mechanism to adjust multi-color emission. However, their poor stability remains a serious problem that has not been solved satisfactorily. Interestingly, QDs glass shows good thermostability and moisture susceptibility. Herein, CsPbBr 3 : x Rb (x = 0, 0.4, 0.6, 0.8) QD glasses which yield tunable emission spectra (475–523 nm) were synthesized successfully via glass crystallization. Most importantly, the as-prepared QDs glasses exhibited ultrastability under various atmospheric, water and heat conditions. Thus, synthesis of a mixed-cation perovskite QDs glass is a new method to achieve stable multi-color emission. They are also expected to become a new generation of photoelectric materials and can be prospectively applied to light-emitting devices. [ABSTRACT FROM AUTHOR]

Since being synthesized, CsPbX 3 (X = Cl, Br or I) quantum dots (QDs) have gained increased interest due to their superior performances in photovoltaic applications. Herein, Sm3+-doped CsPbBr 3 nanocrystallines (NCs) were successfully prepared in zinc borosilicate sodium (ZnO–B 2 O 3 –SiO 2 –Na 2 CO 3 , ZBSN) glass, and the as-prepared glass exhibited a strong red emission, which was attributed to the effects of the energy level transitions in Sm3+. Importantly, white light-emitting diodes (W-LEDs) were prepared by combining the glass with a blue InGaN chip, eliminating the need for a red phosphor to provide the red light, and white light was generated with a high colour rendering index (CRI: 82.6), a low correlated colour temperature (CCT: 4455 K) and colour coordinates in the white light region (0.3547, 0.3234). The glasses show excellent stability at 85 °C and 85% RH. Therefore, the Sm3+-doped CsPbBr 3 NCs glass can be used as a colour converter for application in lighting engineering. [ABSTRACT FROM AUTHOR]

All-inorganic perovskite quantum dots (QDs) have become a hot material in the field of photoelectricity due to their excellent properties, such as high photoluminescence quantum yields (PLQYs), narrow emission wavelengths, and easily controlled PL spectra and particle sizes. However, colloidal perovskite QDs are readily oxidized, degraded in a humid environment, and generated by ion exchange. Here, the CsPb 1-X Sn X Br 2 I QDs were synthesized successfully, which the Sn2+ ions partly replacing Pb2+ to reduce the toxicity of Pb-based perovskite. The tunable PL spectrum and band gap from 2.27 to 2.14 eV were obtained by adjusting the Sn content. Meanwhile, we adopted a simple, green and low-cost approach to encapsulated CsPb 1-X Sn X Br 2 I QDs within solid paraffin, which not only greatly improved the water stability of QDs, but also maintained outstanding luminous intensity after being immersed in water for 20 days. Finally, the while light-emitting diodes (WLEDs) with varying correlated color temperature (CCT), color rendering index (CRI) and luminous efficiency (LE) based on a combination of blue chip, P–CsPb 1-X Sn X Br 2 I QDs and red phosphor were successfully achieved. Low toxicity CsPb 1-x Sn x Br 2 I QDs encapsulated in paraffin with tunble band gap, photoelectric properties and stable for WLED. Image 1 • CsPb 1-X Sn X Br 2 I QDs with tunable band gap and luminescence characteristics were successfully synthesized. • The low toxicity CsPb 1-X Sn X Br 2 I QDs were encapsulated in solid Paraffin. • The as-prepared samples shown excellent water-resistant and presented potential applications in WLED. [ABSTRACT FROM AUTHOR]

Highlights • Sn-doped CsPbBr 3 QDs glasses were successfully synthesized by melt-quenching. • QDs glasses hold excellent luminescent properties while reducing toxicity. • The stability of Sn-doped CsPbBr 3 QDs glasses were greatly improved. • WLED based on Sn-doped CsPbBr 3 QDs glasses realized tunable CCT, CRI and CIE. Abstract CsPbX 3 (X = Cl, Br, I) quantum dots (QDs) are considered to be candidate materials for applications in the field of photoelectric devices due to their remarkable photoelectric properties, such as high photoluminescence quantum yields (PLQYs), narrow emission wavelengths and easy synthesis. However, their instability and high toxicity restrict the further development of QDs. Here, we synthesized Sn-doped CsPbBr 3 perovskite nanocrystals in borosilicate glasses (B 2 O 3 -SiO 2 -ZnO, BSZ) by traditional melt-quenching for the first time. The sample exhibited excellent air stability and thermal stability. Based on these results, white-light-emitting devices were fabricated by incorporating CsPb 0.64 Sn 0.36 Br 3 QDs glasses and commercial red phosphor (CaAlSiN 3 :Eu2+) into a blue LED device. The tunable color coordinates of (0.3179–0.3596, 0.3174–0.3665) and adjustable correlated color temperature (CCT) from 6119 K to 3128 K were successfully achieved in the white light area, which could promote the application of metal ion-doped perovskite QDs in photoelectric devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlight • Epoxy resins act as an encapsulant can solve the stability problem of quantum dots. • Epoxy resins also solve the problem of non-uniform luminescence. • CsPbBr 3 QDs in five different substrates has different luminescence is greatly related to the sizes effect. Abstract To research optical properties of materials for light-emitting-diodes (LEDs) fabrication, CsPbBr 3 quantum dots (QDs) were dispersed in five different substrates to investigate their luminescence. The results show that CsPbBr 3 QDs embedded in glass matrices have superior stability, however, the QDs could not be evenly distributed in the matrices, which resulted in uneven luminescence of the glass. To solve this problem, epoxy resin was introduced as cladding material, which yielded a product that had good stability and consistency. CsPbBr 3 QDs embedded in epoxy resin show great potential for green fluorescent components in LED applications. [ABSTRACT FROM AUTHOR]

Herein, CsPb 2 Br 5 quantum dots (QDs) in glasses under various durations of heat-treatment at 420 °C was investigated. Photoluminescence (PL) spectra of CsPb 2 Br 5 QDs were tuned from 499 to 506 nm and the decay time show a increasing for the structure defect and electron-hole consist in CsPb 2 Br 5 QDs glasses. The CsPb 2 Br 5 glass showed an thermal stability with about 85% emission loss when elevating temperature from 298 K to 433 K. Moreover, The warm white light emitting diode (WLED) was realized through incorporating CaAlSiN 3 :Eu 2+ red phosphor with CsPb 2 Br 5 QDs doped borosilicate glasses on an InGaN blue chip. Finally, we achieved a luminous efficacy of 42.7 lm/W, CCT of 3915 K and CRI of 68.5 under 20 mA current driving. [ABSTRACT FROM AUTHOR]

Recently, more and more scholars synthesised the Mn-doped CsPbX 3 (X = Cl, Br, I) inorganic perovskite quantum dots (PQDs), which exhibited a strong dopant luminescence characteristic of d-d transition of Mn 2+ and dual-color emission. However, Mn-doped CsPbCl 3 PQDs suffer from the instability, which hindered the application of PQDs in optoelectronic devices. Here, we resolve this problem with SiO 2 /Al 2 O 3 monolith (SAM) through a simple sol-gel process and obtained a robust luminescent PQDs-SiO 2 /Al 2 O 3 monolith (PQDs-SAM) with surprising high stability. This is an easy one-pot operation and can be done with large quantities. The composites not only maintain the PQDs remarkable optical properties, but also improve their stability, which is significantly. The Mn-doped CsPbCl 3 PQDs-SAM in powder form is easily mixed into the resins and applied as color-converting layer with curing on blue light-emitting diodes (LED). And above all, the orange PQDs-SAM composite is used as red phosphor and stack on the Ce 3+ :YAG phosphor-in-glass (Ce-PiG) via screen-printing technology (Ce-PiG&R-PQDs-SAM). Whereafter, warm WLED is constructed by blending the Ce-PiG&R-PQDs-SAM materials with the InGaN blue chips. And the constructed WLEDs generate a warm white with an optimal luminous efficacy (LE) of 80.91 l m/W, a high CRI of 83.8, and a low CCT of 4082 K. [ABSTRACT FROM AUTHOR]

All-inorganic CsPbX 3 (X = Cl, Br, I) perovskite quantum dots (QDs) have been investigated owing to their novel optical properties, such as the high photoluminescence (PL) quantum yields (QYs), narrow line-with and tunable wavelength. However, the usual CsPbX 3 QDs suffer from the instability and the anion-exchange reaction, which hinder their applications. In this work, we present an efficient approach towards stable solid-state QDs composites by coating the CsPbX 3 QDs with the mesoporous silica matrixes (QDs/silica). The as-prepared QDs/silica composite not only maintain the QDs remarkable optical properties, but also improve their stability. Meanwhile, the approach also prevents the anion-exchange reaction between perovskite QDs of various halide compositions mixed together in the solid-state. Therefore, these excellent properties enable the QD/silica composite to improve the color rending index (CRI) and the correlated color temperature (CCT) of the traditional phosphor-converted white light-emitting diodes (WLEDs). Herein, for the first time, the red QD/silica composite was used as red phosphor and stacked on the Ce 3+ :YAG phosphor-in-glass (Ce-PiG) via screen-printing technology (Ce-PiG&R-QDs/silica). Subsequently, warm WLEDs were constructed by blending the Ce-PiG&R-QDs/silica materials with the InGaN blue chips. More importantly, the constructed WLEDs generate a warm white with an optimal luminous efficacy (LE) of 56 l m/W, a high CRI of 92, R9 of 90 and a low CCT of 4718 K. These results indicate that the QD/silica composites would have potential practical applications in warm WLEDs. [ABSTRACT FROM AUTHOR]

The addition of MgO had a significant effect on the crystallization behavior of CsPbBr 3. [Display omitted] • The CsPbBr 3 NCs glasses with finely adjustable wavelength (from 522 nm to 533 nm) were realized by tailoring the ratio of MgO. • Although backlit displays made of green and red perovskite quantum dot glass have been reported for many times, the finely adjustable wavelength of green and red perovskite nanocrystals to the color coordinates and its approximation to the standard color coordinates has rarely been studied. With the increasing content of MgO, the color coordinates of CsPbBr 3 NCs are quite close to the Rec.2020 standard, locating the CIE at (0.1772, 0.7773). • Optical properties changed obviously owing to the network modification effect of MgO. • The stabilities of CsPbBr 3 NCs in terms of water, thermal and laser have improved obviously benefiting from the B-Si-Zn glass matrix and the addition of MgO. • The color gamut of the assembled light conversion films can cover about 129% and 96% of that of NTSC 1953 and Rec.2020, respectively. All-inorganic perovskite CsPbX 3 (X = Cl, Br, I) nanocrystals (NCs) are becoming a critical material for the narrow-band fluorescent material in the field of backlit displays. Herein, CsPbBr 3 (CPB) NCs glasses with finely adjustable wavelength were successfully prepared in the narrow range of 522–533 nm by controlling the content of MgO in borosilicate glass matrix. It is surprising that the addition of MgO enhances the optical properties of CPB NCs, as well as improves their stability. Furthermore, in order to verify its application in backlight display, the light conversion film with a color gamut of up to 129% of NTSC 1953 was successfully prepared, displaying more details of object color on the liquid crystal display (LCD) screen compared with commercial one. These results undoubtedly provide a broad road for wide color gamut backlight display with respect to perovskite nanomaterials. [ABSTRACT FROM AUTHOR]

In this paper, CsPbX 3 (X = Br, I) quantum dots glasses solid materials are fabricated based on the melting and heat-treatment methods. A series of characterization measurements are carried out to research the microscopic morphology and luminescent properties of solid materials. Finally, the multicolour light-emitting devices (LEDs) are constructed by adhesion commercial InGaN blue chip with as-prepared glasses. [ABSTRACT FROM AUTHOR]

Highlights: [•] The CuGaS2 quantum dots doped sodium borosilicate glass was prepared by sol–gel methods. [•] The obtained glass was investigated by XRD, (S)TEM and XPS. [•] Tetragonal crystalline phase of CuGaS2 quantum dots with spherical shape were formed uniformly in the glass matrix. [•] The third-order optical nonlinearity was investigated by Z-scan technique. [ABSTRACT FROM AUTHOR]

Highlights: [•] The quantum yield of the obtained ternary AgInS2 QDs was up to 62% with the emission peak of 642nm under the excitation of 460nm. [•] Colorful luminescent Ag–Zn–In–S QDs were obtained by adding Zn salts directly as well as Ag and In precursors. [•] The obtained highly luminescent quantum dots showed promising applications in the white light emitting diodes (W-LED). [•] The electroluminescence (EL) of AgInS2 QDs was observed in QD-LED device. [ABSTRACT FROM AUTHOR]

Abstract: Copper quantum dots embedded in sodium borosilicate glass matrix were fabricated and analyzed in terms of their structural, chemical, and optical properties. X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses revealed that copper quantum dots were in face-centered-cubic crystalline phase and in the metallic state. Size and distribution of the quantum dots were measured by transmission electron microscopy (TEM) as well as high-resolution transmission electron microscopy (HRTEM). The results showed spherical shape have formed uniformly in the glass, and the size of these quantum dots were range from 1.5 to 5nm with the average particle size about 2.7nm. The third-order nonlinear optical properties of copper quantum dots doped glass were investigated by using Z-scan technique at the wavelength of 800nm with femtosecond Ti: sapphire laser radiation. The value of third-order optical nonlinear susceptibility χ (3) of the glass was estimated to be 2.41×10−11 esu. [Copyright &y& Elsevier]

Abstract: The sodium borosilicate glass doped with Cu7.2S4 quantum dots was prepared by using both sol–gel and atmosphere control methods. The formation mechanism and the microstructure of the glass were examined using differential thermal analysis and thermal gravimeter (TG-DTA), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), energy dispersive X-ray spectra (EDX), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED). The results revealed that Cu7.2S4 quantum dots in orthorhombic crystal system had formed in the glass, and the size ranged from 9nm to 21nm. In addition, Z-scan technique was used to measure the third-order optical nonlinearities of the glass. The results indicated that the third-order optical nonlinear refractive index γ, the absorption coefficient β, and the susceptibility χ (3) of the glass were 1.11×10−15 m2/W, 8.91×10−9 m/W, and 6.91×10−10 esu, respectively. [Copyright &y& Elsevier]

• TS-1 with mesoporous structure are used as the carrier of perovskite firstly. • The hollow structure of TS-1 isolates the inner from the external environment. • TS-1 is one of the few materials with hydrophobic in molecular sieves. • The PLQYs of CsPbX 3 -TS-1 is excellent (up to 74%). • The matched WLEDs show luminous efficiency of 95 lm/W. CsPbX 3 (X = Br, I) quantum dots (QDs) have gradually become the star materials in light-emitting diodes (LED), but its stability has a big impact on development. Here, a variety of novel CsPbX 3 -TS-1 nanocomposites have been fabricated and the luminescence wavelength can be tunable by varying the halide nanocomposites (Br, I). What's particularly nice is that the original photoluminescence quantum yield (PLQY) of CsPbBr 1 l 2 QDs approaches 82% and it still has close to 74% after being combined with TS-1. Besides, the nanocomposites enhance stability resisting moisture, thermal stressing and light. In addition, a 460 nm InGaN blue chip, YAG:Ce3+ and CsPbBr 1 I 2 -TS-1 were equipped with white light emitting diodes (WLEDs), with a luminous effect of 95 lm/W, a color rendering index of 80, and a color temperature of 5144 K. Meanwhile, wide color gamut (116% of the National Television Standards Committee, 86.3% of the ITU-R Recommendation BT. 2020) and great chromaticity coordinate (0.3425, 0.3408) are realized. This is a very important step to open up the awkward situation of the practical application of perovskite QDs materials in LED. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using OA to etch surface smooth original α-Al 2 O 3 wafer to make the surface appear pore structure. • The PL intensity of CsPbBr 3 @α-Al 2 O 3 composite material exposure to the air after 28 days can maintain over 50%. • The PLQY of CsPbBrI 2 @α-Al 2 O 3 composite material can reach 58%. • The colour purity of CsPbBr 3 @α-Al 2 O 3 and CsPbBrI 2 @α-Al 2 O 3 achieve 97.1% and 99.8%, respectively. • The prepared blue, green, red composites possess a wide color gamut of 114%. Recently, perovskite has received extensive attention due to their excellent photoelectric properties, while the instability of perovskite quantum dots (PQDs) has always troubled us. Herein, we proposed a simple coating mechanism to protect PQDs. Using oleic acid (OA) for etching α-Al 2 O 3 wafer to make the surface appear pore structure, and the PQDs was coated within the modified α-Al 2 O 3 wafer, thereby improving the stability of PQDs. The CsPbX 3 @α-Al 2 O 3 composite material can achieve the emission of blue-green–red (436 nm to 636 nm) through adjustable luminescence wavelength. The photoluminescence (PL) intensity of CsPbBr 3 @α-Al 2 O 3 composite material exposure to the air after 28 days can maintain over 50%. It is worth noticing that the photoluminescent quantum yield (PLQY) of CsPbBrI 2 @α-Al 2 O 3 composite material can reach 58%, the colour purity of CsPbBr 3 @α-Al 2 O 3 and CsPbBrI 2 @α-Al 2 O 3 achieve 97.1% and 99.8%, respectively. It was due to the high colour purity of the composite materials can the selected CIE colour coordinate monochromatic light encompassed 114% of NTSC colour gamut. Moreover, the warm white light-emitting diode (WLED) yielded bright natural white light and showed the luminous efficiency (LE) of 86.58 lm/W, colour rendering index (CRI) of 86.9, correlated colour temperature (CCT) of 4602 K. The LE and CRI reaches a relatively balanced value, which showed that this composite material has a certain development prospect in the WLED field. [ABSTRACT FROM AUTHOR]

All inorganic CsPbX 3 (X = Cl, Br, I) perovskite quantum dots (QDs) have been widely reported. However, the poor stability of CsPbX 3 QDs limits their application in the field of optoelectronics. In this work, CsPbX 3 QDs were prepared by the hot injection strategy. We compounded CsPbX 3 QDs with mica to improve stability. A series of novel CsPbX 3 @mica composites with high thermal stability and light radiation stability were successfully fabricated and the narrow full width at half maximum (FWHM) of blue, green and red emissions are ~17 nm, ~21 nm and ~37 nm, respectively. What's more, the photoluminescence quantum yield (PLQY) of CsPbBr 3 @mica composite is 38.5%. Notably, the white light-emitting diodes (wLED) device can be manufactured by coupling the red-emitting CsPbBr 1 I 2 @mica composite material and commercial phosphor YAG: Ce3+ with the InGaN chip to produce bright natural white light. Meanwhile, CsPbX 3 @mica composites can be used as color conversion materials to construct a LED device, which exhibits a wide color gamut covering up 115.7% of National Television System Committee (NTSC). This present work provided novel CsPbX 3 @mica composites and could bring the potential inspiration in backlit display and lighting applications. [Display omitted] • The novel CsPbX 3 @mica composites with tunable emission in 468–630 nm were successfully fabricated. • The CsPbBr 3 @mica composite has excellent thermal and light irradiation stability. • The wLED can be manufactured by coupling CsPbBr 1 I 2 @mica and YAG:Ce3+ with InGaN chip to produce bright natural white light. • The CsPbX 3 @mica composites show a wide color gamut (115.7% NTSC). [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide perovskite quantum dots (QDs) have attracted widespread attention due to unique photoelectric properties. However, blue-emitting (CsPbCl x Br 3−x , 0 < x ≤ 3) QDs have poor stability and low photoluminescence quantum yields (PLQY), which limits its application in perovskite based light-emitting diodes (LEDs). The chlorine-free CsPbBr 3 QDs have fewer crystal defects and a more stable crystal structure. Here, we prepared CsPbBr 3 QDs with adjustable photoluminescence (PL) (489–519 nm) by controlling the reaction temperature and composited it with natural mineral halloysite (Hal) nanotubes. The as-prepared CsPbBr 3 @Hal (100 °C) have high PL intensity, bright blue emission and enhanced stability. Under an open ambient condition, the CsPbBr 3 @Hal (100 °C) can still maintain 92.4% of original PL intensity after 60 days of storage. In addition, after 280 h of continuous irradiation with 365 nm UV lamp, its PL intensity still maintained 71%. Finally, a white LED (WLED) fabricated by incorporating the CsPbBr 3 @Hal (100 °C) and commercial red CaAlSiN 3 : Eu2+ phosphor on the 395 nm InGaN blue-violet chip showed the CIE chromaticity coordinates of (0.3358, 0.3331). This work provides a new way for the synthesis and application of blue-emitting CsPbBr 3 perovskite materials in WLEDs and display devices. [Display omitted] • Samples prepared at different temperatures have high PL intensity and stability. • The CsPbBr 3 @HNTs (100 °C) has bright blue emission and perfect stability. • The WLEDs made by CsPbBr 3 @HNTs produce high quality white light and are adjustable. [ABSTRACT FROM AUTHOR]

CsPbX 3 (X=Cl, Br or I) has been studied due to its outstanding optical properties. However, it is difficult to use in practical applications due to its poor stability. Currently, there are interesting examples of CsPbX 3 compounded with glass substrates. The quantum efficiencies of CsPbX 3 NC glasses are relatively low. In this work, we propose a simple method for fabricating Yb3+-doped CsPbI 3 quantum dots in glass via a conventional melt quenching technique. It was found that the CsPbI 3 NC glasses had blue-shifted emission with increasing amounts of the Yb3+ dopant. The photoluminescence quantum yield (PLQY) of CsPbI 3 : Yb3+ NC glass reached from 20% to 66.7%. And the CsPbI 3 : Yb3+ NC glass exhibited good thermal stability. Moreover, the experimental results showed th*at the CsPbI 3 : Yb3+ glass could match the properties of a commercial fluorescent powder used to make white LEDs (WLEDs). [ABSTRACT FROM AUTHOR]

Cd2+ doped CsPbBr 3 perovskite quantum dots were synthesized in borosilicate glass for the first time by traditional melting method. By X-Ray Diffraction (XRD) and high resolution electron microscopy analysis, it was proved that Cd2+ successfully entered the perovskite lattice structure. The samples have good optical properties, high photostability, chemical stability, thermal stability and water stability. On this basis, CsPb 0.7 Cd 0.3 Br 3 QDs glass, commercial red phosphor (CaAlSiN 3 :Eu2+) and blue light chip were coupled to produce white LED devices. This discovery opens up a new way for the application of metal ion-doped perovskite QDs glass in optoelectronic devices. • A series of Cd2+ doped CsPbBr 3 QDs glasses with high PL intensity, quantum efficiency and excellent stability were prepared. • The WLEDs made by CsPb x Cd 1-x Br 3 QDs glass produce high quality white light, adjustable from cold to warm white light. • Compared with the original CsPbBr 3 QDs glass, the quantum efficiency of Cd2+ doped glass has been improved greatly. [ABSTRACT FROM AUTHOR]

• Ti-doped CsPbI 3 QDs were successfully prepared in borosilicate glass matrix. • Ti-doped CsPbI 3 QDs@glasses possess superior optical performance. • The water/thermal stability of Ti-doped CsPbI 3 QDs@glasses are excellent. • The wLED based on CsPb 1− x Ti x I 3 QDs@glasses realized outstanding LE and CRI. • LED devices based on CsPb 1− x Ti x I 3 QDs@glasses well satisfy plant growth. Currently, the application of all-inorganic cesium lead halide perovskite (CsPbX 3 , X = Cl, Br, I) quantum dots (QDs) is limited due to toxicity of lead and poor ambient stability. In our work, a series of Ti-doped CsPbI 3 QDs were successfully prepared in borosilicate glass (SiO 2 -B 2 O 3 -ZnO) by the melt quenching and in situ crystallization technique. The samples showed excellent water/thermal stability, and the tunable emission (650–695 nm) was controlled by different Ti contents and heat treatment temperatures. In particular, the optical properties of CsPb 1− x Ti x I 3 QDs@glasses (x ≤ 0.5) are superior to those of pristine CsPbI 3 QDs@glass. As a result, the wLED was assembled using red-emitting CsPb 1− x Ti x I 3 QDs@glasses and yellow-emitting Ce3+:YAG phosphor under excitation of InGaN blue chip, which demonstrated an outstanding luminous efficiency of 102.44 lm/W, a high color rendering index of 80.6. Particularly, Ti-doped CsPbI 3 QDs@glasses with red and far-red light are combined with a blue-chip to assemble an LED device, which exactly satisfies the lighting conditions of plant growth. [ABSTRACT FROM AUTHOR]