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Multi-band emission luminescence materials are of great significance owing to their extensive application in diverse fields. In this research, we successfully prepared a series of Pr3+-doped Ca3Al2O6 multi-band emission phosphors via a high-temperature solid-state method. The phase structure, morphology, luminescence spectra and decay curves were investigated in detail. The Ca3Al2O6:Pr3+ phosphors can absorb blue lights and emit lights in the 450–750 nm region, and typical emission bands are located at 488 nm (blue), 525–550 nm (green), 611–614 nm (red), 648 nm (red) and 733 nm (deep red). The influence of the Pr3+ doping concentration was discussed, and the optimal Pr3+ doping concentration was determined. The impacts of charge compensator ions (Li+, Na+, and K+) on the luminescence of Pr3+ were also investigated, and it was found that all the charge compensator ions contributed positively to the emission intensity. More importantly, the emission intensity of the as-prepared phosphors at 423 K can still maintain 65–70% of that at room temperature, and the potential application for pc-LED was investigated. The interesting results indicate that the prepared phosphors may serve multifunctional and advanced applications. [ABSTRACT FROM AUTHOR]

We report a rapid synthesis method for producing CsSnCl3:Mn2+ perovskites, derived from SnF2, and investigate the effects of rapid thermal treatment on their photoluminescence properties. Our study shows that the initial CsSnCl3:Mn2+ samples exhibit a double luminescence peak structure with PL peaks at approximately 450 nm and 640 nm, respectively. These peaks originate from defect-related luminescent centers and the 4T1→6A1 transition of Mn2+. However, as a result of rapid thermal treatment, the blue emission is significantly reduced and the red emission intensity is increased nearly twofold compared to the pristine sample. Furthermore, the Mn2+-doped samples demonstrate excellent thermal stability after the rapid thermal treatment. We suggest that this improvement in photoluminescence results from enhanced excited-state density, energy transfer between defects and the Mn2+ state, as well as the reduction of nonradiative recombination centers. Our findings provide valuable insights into the luminescence dynamics of Mn2+-doped CsSnCl3 and open up new possibilities for controlling and optimizing the emission of rare-earth-doped CsSnCl3. [ABSTRACT FROM AUTHOR]

The fundamental photophysics involved in the doping effect of zero-dimensional (0D) lead-free tin-halide perovskites (Cs4SnX6, X = Br and I), especially the dynamics of self-trapped excitons (STEs), is crucial for their practical applications. Here, we proposed the use of Mn2+ doping to realize efficient emission from the STEs in Cs4SnBr6. The Mn2+-doped Cs4SnBr6 exhibits an enhanced photoluminescence (PL) quantum yield of up to ∼75.8%, a broadened emission spectrum, and improved thermal stability. The experimental observations combined with first-principles calculations reveal that the significant PL enhancement originates from the enhanced electron–phonon coupling and the increased binding energies of STEs, as a consequence of the large distortion of [SnBr6]4− octahedra induced by Mn2+ doping. In addition, it was verified that the color tuning of Mn2+-doped Cs4SnBr6 is achieved by the competitive transfers of free excitons to STE states and Mn2+ sites based on time-resolved and temperature-dependent PL measurements. The Mn2+-doped Cs4SnBr6 assembled into commercial UV-LED chips exhibits strong white light emission with a color temperature of 6346 K. Our findings not only provide deep insight into the dynamics of STEs in Mn2+-doped Cs4SnBr6 but also open new horizons for manipulating and optimizing the emission of STEs in 0D perovskites, thereby laying a foundation for developing white LEDs based on 0D perovskites. [ABSTRACT FROM AUTHOR]

The effect of a-SiCxNy:H encapsulation layers, which are prepared using the very-high-frequency plasma-enhanced chemical vapor deposition (VHF-PECVD) technique with SiH4, CH4, and NH3 as the precursors, on the stability and photoluminescence of CsPbBr3 quantum dots (QDs) were investigated in this study. The results show that a-SiCxNy:H encapsulation layers containing a high N content of approximately 50% cause severe PL degradation of CsPbBr3 QDs. However, by reducing the N content in the a-SiCxNy:H layer, the PL degradation of CsPbBr3 QDs can be significantly minimized. As the N content decreases from around 50% to 26%, the dominant phase in the a-SiCxNy:H layer changes from SiNx to SiCxNy. This transition preserves the inherent PL characteristics of CsPbBr3 QDs, while also providing them with long-term stability when exposed to air, high temperatures (205 °C), and UV illumination for over 600 days. This method provided an effective and practical approach to enhance the stability and PL characteristics of CsPbBr3 QD thin films, thus holding potential for future developments in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Amorphous silicon oxynitride (a‐SiNxOy) film is a kind of new luminescent material, which exhibits highly efficient light emission from luminescent N–Si–O defect states. In this work, the measurements of steady‐state photoluminescence (SSPL), temperature‐dependent photoluminescence (TDPL), and nanosecond time‐resolved photoluminescence (ns‐TRPL) are combined to further verify the role of luminescent N–Si–O defect states on the performance of photoluminescence (PL), electro‐luminescence (EL), and optical gain, etc., for both intrinsic and doped a‐SiNxOy films. The results indicate that both PL and EL originate from luminescent N–Si–O defect states, which is totally different behavior from that observed from band tail states in normal amorphous semiconductors. In the case of device applications, the properties of optical gain in an a‐SiNxOy/SiO2 waveguide are investigated. Based on the signal of amplified spontaneous emission (ASE) coming from the edge of the waveguide, an optical gain coefficient higher than 100 cm−1 is obtained by using variable stripe length (VSL) measurements. For another application example, it is found that radiative recombination via luminescent N–Si–O defect states can also contribute to the EL observed from an n‐a‐SiNxOy/p‐Si heterojunction LED, in which the light emission power efficiency is determined to be five times higher than that in an a‐SiNxOy MIS LED. [ABSTRACT FROM AUTHOR]