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In the current work, a facile ion-solution spraying strategy was employed for one-step fabrication of CsPbBr3 perovskite thin films under atmosphere. The dependences of sample properties on annealing parameters (toleration temperature and duration time) were investigated in detail. As the results suggested, the sample prepared at 200 °C for 15 min featured better properties than others. The sample displayed a cubic phase with good crystallinity, a dense and compact morphology, a bandgap energy of 2.289 eV, and an average decay lifetime of 55.536 ns. Furthermore, the sample presented a Br-rich state, which was favorable for the carrier behavior and structure stability. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) Cu2+–Mn2+ co-doped CsPb2(ClBr)5 nanocrystals (NCs) with various Cu/Mn molar ratios were synthesized by a simple one-pot method at room temperature. Additionally, we encapsulated C3H9SiCl to protect the co-doped CsPb2(ClBr)5 NCs from moisture. The analysis of the structure and composition confirmed the phase and chemical composition of the 2D co-doped CsPb2(ClBr)5 NCs. Steady-state and time-resolved photoluminescence (PL) spectroscopy revealed the enhanced optical properties of the 2D co-doped CsPb2(ClBr)5 NCs. Meanwhile, the optical properties of Cu2+–Mn2+ co-doped NCs presented the good thermal stability even after 36 days. The photoluminescence quantum yields (PLQYs) related to the Mn2+ emission of the 2D co-doped CsPb2(ClBr)5 NCs increased to 97.36% at a Cu/Mn molar ratio of 0.05/1. Furthermore, a prototype white light-emitting device (WLED) was successfully assembled by combining orange‒red Cu2+–Mn2+ co-doped CsPb2(ClBr)5 NCs, a CsPbBr3 film, and a 365 nm commercial UV chip; this prototype confirms its potential for a wide range of applications in general lighting. [ABSTRACT FROM AUTHOR]

In this work, a facile solution based on the supersaturated crystallization principle combined with an ion exchange strategy was employed for the preparation of all-inorganic lead halide perovskite CsPbX3 quantum dots (X = Cl, Br, I, and their combinations) under an ambient atmosphere. As the results showed, with the progression of Br–Cl and Br–I ion exchange, the green emission of pure CsPbBr3 gradually turned to cyan and blue, yellow, and red, respectively. Thus, the emission featured a broad wavelength range from 472 nm to 638 nm. With regard to the morphology, the as-synthesized quantum dots were all spherical and monodisperse, and the crystal size increased from the blue to the red samples. Furthermore, the chemical composition investigated by energy-dispersive x-ray spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) confirmed the successful Br–Cl or Br–I ion exchange, and the obtained samples were expressed as CsPbBr1.9Cl1.1, CsPbBr2.1Cl0.9, CsPbBr3, CsPbBr1.7I1.3, and CsPbBr0.9I2.1 for blue, cyan, green, yellow, and red samples, respectively. In future work, the as-synthesized samples will be investigated for use in an optoelectronic device application. [ABSTRACT FROM AUTHOR]

We report a simple and low-cost at room temperature and atmospheric pressure synthetic method for highly stable and photoluminescence (PL) Mn2+-doped CsPb(Br/Cl)3 nanocrystal (NCs) thin films with high Mn-to-Pb feed ratio. The XRD, EDS, and XPS results confirm that Mn ions can be significantly doped in host CsPb(Br/Cl)3 NCs. PL spectra show multi-color luminescence, which is related to host exciton and Mn2+ dopant state emission, respectively. In addition, the optical properties of Mn2+-doped NCs present the good thermal stability even after 35 days. Furthermore, light-emitting diodes were constructed by employing as-prepared Mn2+-doped NCs (Mn-to-Pb feed ratio of 5:1) and CsPbBr3 with the commercial UV chip, demonstrating that Mn2+-doped NCs are applicable to the color converters for the potential field of lighting and display. [ABSTRACT FROM AUTHOR]

In the present work, Cu2ZnSnS4 (CZTS) thin film is successfully prepared by the calcinated nanocrystals with screen‐printing approach. The dependences of the obtained samples' properties on the annealing parameters of temperature and time are well studied via X‐ray diffraction, Raman, field emission scanning electron microscopy, ultraviolet‐visible‐infrared (UV‐vis‐IR) spectroscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy treatments. The results suggested that the best performances of prepared sample can be obtained at 600 °C for 20 min. The obtained sample features a kesterite CZTS phase, a surface morphology consisting of microns nanoparticles, a Cu‐rich and Zn‐rich chemical composition, and an ideal band gap of 1.4 eV. Additionally, the impurity phase of copper sulfide resulting from Cu‐rich composition is needed to further improve in the next work. [ABSTRACT FROM AUTHOR]

The high color rendering index of warm white light-emitting diode (WLED) was fabricated using LuAG: Ce3+ PiG coated CaAlSiN3: Eu2+ phosphor film as converted materials. The LuAG: Ce3+ PiG and CaAlSiN3: Eu2+ phosphor film was prepared by low-temperature co-sintering and spin coating route, respectively. In this work, the thermal stability of LuAG: Ce3+ PiG through the thermal shock test was discussed. After that, the optical properties of Lu2.94−xYxAl5O12: 0.06Ce3+ (x = 0, 0.2, 0.4, 0.6, 0.8) PiG coated CaAlSiN3: Eu2+ phosphor film converted WLEDs were investigated. When x value is 0.4, it exhibits a color rendering index of 94, correlated color temperature of 3087 K and luminous efficiency of 62 lm/W under 20 mA current driving. The package method has excellent developing potential for residential lighting applications. [ABSTRACT FROM AUTHOR]

N-Mn codoped ZnO films were prepared by ultrasonic spray pyrolysis (USP) to search for the room-temperature ferromagnetism. Structural, magnetic and electrical properties of ZnO-based films were investigated. Rapid thermal processing was conducted to explore the influence of the post-treatment on magnetic and electrical properties of ZnO-based films. The results show that magnetic properties of Mn-doped ZnO films by USP strongly depend on the acceptor doping and annealing treatments, which is consistent with the theoretical prediction that hole carriers might be necessary to induce ferromagnetism in ZnO:Mn system. [ABSTRACT FROM AUTHOR]

In this paper, green Y(AlGa)O:0.06Ce phosphors were prepared by conventional solid-state reaction. The crystal structures, the influence of Ga concentration on the photoluminescence, thermal stability and reliability properties of the phosphors were studied. The PL emission bands of Y(AlGa)O:0.06Ce showed blue shift from 545 nm to 525 nm with increasing Ga content (x value) under excited at 460 nm. The thermal stability of Y(AlGa)O:0.06Ce phosphor is hindered by adding Ga. As the temperature increases from 300 to 500 K, the PL intensity of Y(AlGa)O:0.06Ce and Y(AlGa)O: 0.06Ce phosphor decreases by 11.11 and 16.57 %, respectively. Reliability test results show that the relative PL intensity of Y(AlGa)O:0.06Ce phosphor decrease to from 99.76 to 95.37 % with x value increased from 0.15 to 0.35 after the ambient condition of 85 °C/RH 85 % for the exposure time of 168 h. And the relative PL intensity of Y(AlGa)O:0.06Ce phosphor decrease to from 99.53 to 91.78 % after soaking into boiled water for 4 h. It can be summarized that the addition of Ga deteriorates the thermal stability as well as the reliability of the phosphors slightly. [ABSTRACT FROM AUTHOR]

Nowadays, Mn-doping is considered as a promising dissolution for the heavy usage of toxic lead in CsPbX3 perovskite material. Interestingly, Mn-doping also introduces an additional photoluminescence band, which is favorable to enrich the emission gamut of this cesium lead halide. Here, a solution spraying strategy was employed for the direct preparation of CsPbxMn1−x(Br,Cl)3 film through MnCl2 doping in host CsPbBr3 material. The possible fabrication mechanism of the provided approach and the dependences of material properties on Mn-doping were investigated in detail. As the results shown, Pb was partially substituted by Mn as expected. With the ratio of PbBr2:MnCl2 increasing from 3:0 to 1:1, the obtained film separately featured green, cyan, orange-red and pink-red emission, which was caused by the energy transferring process. Moreover, the combining energy of Cs, Pb, and Mn gradually red-shifted resulted from the formation of Cs-Cl, Pb-Cl and Mn-Br coordination bonding as MnCl2 doping increased. In addition, the weight of short decay lifetime of prepared samples increased with the doping rising, which indicated a better exciton emission and less defect-related transition. The aiming of current work is to provide a new possibility for the facile preparation of Mn-doping CsPbX3 film material. [ABSTRACT FROM AUTHOR]

Nowadays, Mn-doping is considered as a promising dissolution for the heavy usage of toxic lead in CsPbX 3 perovskite material. Interestingly, Mn-doping also introduces an additional photoluminescence band, which is favorable to enrich the emission gamut of this cesium lead halide. Here, a solution spraying strategy was employed for the direct preparation of CsPb x Mn 1-x (Br,Cl) 3 film through MnCl 2 doping in host CsPbBr 3 material. The possible fabrication mechanism of the provided approach and the dependences of material properties on Mn-doping were investigated in detail. As the results shown, Pb was partially substituted by Mn as expected. With the ratio of PbBr 2 :MnCl 2 increasing from 3:0 to 1:1, the obtained film separately featured green, cyan, orange-red and pink-red emission, which was caused by the energy transferring process. Moreover, the combining energy of Cs, Pb, and Mn gradually red-shifted resulted from the formation of Cs-Cl, Pb-Cl and Mn-Br coordination bonding as MnCl 2 doping increased. In addition, the weight of short decay lifetime of prepared samples increased with the doping rising, which indicated a better exciton emission and less defect-related transition. The aiming of current work is to provide a new possibility for the facile preparation of Mn-doping CsPbX 3 film material.