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Mn‐doped CsPbCl3 perovskite nanocrystal (PeNC) glass was prepared by melt quenching and in situ crystallization. Under the protection of robust glass, PeNCs exhibit excellent moisture resistance and thermal stability. The combination effect of thermal quenching and energy transfer of exciton to Mn2+ enables its promising applications in the field of temperature sensor. Interestingly, by matching with ultraviolet chips, all‐inorganic blue‐red emitting conversion device consisting of PeNC glass was prepared for light‐emitting diodes (LEDs), which can meet the light requirements of plant growth. The cultivation results indicated that the growth of cabbages using PeNC plant cultivation LEDs was greater than those cultivated using commercial w‐LEDs (white light‐emitting diodes). Therefore, Mn‐doped CsPbCl3 PeNCs can be used as a new generation of solid fluorescent materials in the field of indoor plant cultivation LEDs. [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]

A novel red‐emitting phosphor Ca5Ga6O14:Eu3+ has been synthesized using solid‐state method. The excitation and emission spectra show that the phosphor can emit the red light with the main peak at 611 nm under excitation of the 280 and 393 nm UV chip and the optimal Eu3+ concentration is determined to be x = 0.07. Analysis of emission spectrum shows that Eu3+ occupy the center of noninversion symmetry. With the increase of Eu3+ doping concentration, the decay time is prolonged due to deeper energy trap arising from nonequivalent substitution. Additionally, the measured thermal stability with 0.539 eV activation energy and calculated 90.5% color purity of optimal phosphor indicate that the phosphor has an enormous application potential in w‐LEDs industry. [ABSTRACT FROM AUTHOR]

We successfully synthesized Mn‐doped CsPbBr0.5I2.5 nanocrystals (NCs) using a traditional hot injection method. The Mn‐doped CsPbBr0.5I2.5NCs have very good luminescence propertie. Unfortunately, they can only be dissolved in nonpolar solvents, and they suffer from the effect of air instability, thermal instability, and water instability. In this study, we used mesoporous SiO2 and Al2O3 coatings to improve the air stability and water stability of these nanocrystals, inhibit the loss of Mn2+. The prepared composite material not only maintains the excellent optical properties of the NCs, but also the most important is to significantly improve the stability of the NCs. Importantly, Mn‐doped CsPbBr0.5I2.5NCs can also be used as a red fluorescent material, with green CsPbBr3NC glass‐emitting white LED under the excitation of an InGaN blue chip. [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]

A double perovskite‐type substrate of La2MgGeO6 (LMGO) was successfully synthesized via a high‐temperature solid‐state reaction method and was codoped with Mn4+ and Dy3+ to form a new deep‐red phosphor (LMGO:Mn4+,Dy3+) for artificial plant growth light‐emitting diodes (LEDs). This extraordinary phosphor can exhibit strong far‐red emission with a maximum peak at 708 nm between 650 and 750 nm, which can be ascribed to the 2Eg → 2A2 g spin‐forbidden transition of Mn4+. The X‐ray diffraction (XRD) patterns and high‐resolution transmission electron microscopy (HRTEM) clarified that the La3+ sites in the host were partly replaced by Dy3+ ions. Moreover, we discovered energy transfers from Dy3+ to Mn4+ by directly observing the significant overlap of the excitation spectrum of Mn4+ and the emission spectrum of Dy3+ as well as the systematic relative decline and growth of the emission bands of Dy3+ and Mn4+, respectively. With the increase in the activator (Mn4+) concentration, the relationship between the luminescence decay time and the energy transfer efficiency of the sensitizer (Dy3+) was studied in detail. Finally, an LED device was fabricated using a 460 nm blue chip, and the as‐obtained far‐red emitting LMGO:Mn4+,Dy3+ phosphors for Wedelia chinensis cultivation. As expected, the as‐fabricated plant growth LED‐treated Wedelia chinensis cultured in the artificial climate box with overhead LEDs demonstrated that after 28 days of irradiation, the average plant growth rate and the total chlorophyll content were better than those of specimens cultured using the commercial R‐B LED lamps, indicating that the as‐prepared phosphor could have a potential application in the agricultural industry. [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]

The sodium borosilicate glass doped with CuInS2 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, X-ray powder diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning transmission electron microscopy, energy dispersive X-ray spectra, high-resolution transmission electron microscopy, and selected area electron diffraction. The results revealed that CuInS2 quantum dots in a tetragonal crystal system had formed uniformly in the glass, and the size distribution of these quantum dots generally ranged from 5 to 15 nm. In addition, Z-scan technique was used to measure the third-order optical nonlinearities of the glass. The results indicated that the glass has excellent third-order optical nonlinearities, and thus will have potential applications in the field of nonlinear optics. [ABSTRACT FROM AUTHOR]