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CsPbBr3 exhibits strong green emission, but its toxicity limits its widespread application. Lead-free perovskites exhibit excellent optoelectronic properties while eliminating the toxicity of lead; at the same time, doping substitution is an effective means to further optimize the optoelectronic performance of perovskites. In this work, zinc(II) is chosen to achieve heterovalent substitution in the copper(I) based perovskite Cs3Cu2Cl5 and obtain strong green luminescence. The photoluminescence quantum yield (PLQY) reached 70.19% at an optimal doping concentration, which is twice the PLQY of undoped Cs3Cu2Cl5 and much higher than that of most doped lead-free perovskites. Furthermore, a white light emitting diode (WLED) was fabricated with doped Cs3Cu2Cl5:0.20 Zn2+ as a green phosphor, commercial blue phosphor Sr(PO4)Cl:Eu+, and commercial red phosphor CaAlSiN3:Eu2+. The color rendering index (CRI) is 95.8, while the correlated color temperature (CCT) is 4573 K, which is much better than that of the WLED fabricated with CsPbBr3. This research provides important guidance on the fabrication of green light emission Zn-doped Cs3Cu2Cl5 instead of toxic CsPbBr3 and has potential in WLED lighting. [ABSTRACT FROM AUTHOR]

A novel Mn2+ doped ScTaO4 phosphor was synthesized through a high temperature solid state method and its photoluminescence properties were systematically investigated. The ScTaO4:Mn2+ phosphor exhibited two emission bands centered at 478 nm and 661 nm under UV excitation, attributed to the self-activated emission of the host and the 4T1 → 6A1 transition emission from doped Mn2+ ions, respectively. Through optimizing the concentration of doped Mn2+ ions, white light emission was achieved. Meanwhile, the temperature-dependent luminescence spectra of the ScTaO4:Mn2+ phosphor (in the range from 298 K to 523 K) revealed significantly different thermal quenching behaviors between the host and Mn2+ ions, which cause a notable change in the fluorescence intensity ratio of the host versus Mn2+ ions and enable high absolute and relative sensitivities, with maximum values of 0.0172 K−1 and 2.1% K−1 at 523 K, respectively. The results indicated that the as-prepared STO:Mn2+ phosphor can be a potential candidate material for high temperature optical thermometry. [ABSTRACT FROM AUTHOR]

Transition metal ion and/or rare earth ion doped CsPbCl3 nanocrystals (NCs) have attracted extensive attention due to their high combined emission efficiency characteristics. Their high-throughput preparation is of great significance for future industrialization that is still a challenge based on existing batch reaction technologies. Herein, we demonstrate a high-throughput preparation method of Mn2+-doped CsPbCl3 NCs based on a fluidic channel reactor. The as-prepared NCs show vivid yellowish-orange emission at 600 nm and high photoluminescence quantum yield (PLQY) of 63.3%. Meaningfully, due to the closer bond between surface ligands and NCs, NCs prepared by this method show better water durability than NCs obtained using the traditional hot injection method. Finally, a WLED with a high color rendering index (CRI) of 94 and a low correlated color temperature (CCT) of 3626 K was fabricated by combining the as-prepared yellowish-orange Mn-doped CsPbCl3 with the BaMgAl10O17:Eu2+ (BAM:Eu2+) blue phosphor and CaAlSiN3:Eu2+ (CASN:Eu2+) red phosphor on a 375 nm ultraviolet chip. These findings suggest that the Mn-doped CsPbCl3 prepared by the fluidic channel reaction is suitable for WLEDs. Our work paves the way for achieving a continuous, large-scale preparation of perovskite NCs by a fluidic channel reaction for the development of their WLED solid state lighting applications. [ABSTRACT FROM AUTHOR]

A green phosphor Sr2ZnGe2O7:Mn2+ with a melilite structure was prepared using a high‐temperature solid‐state reaction. When the 535 nm emission was monitored, the excitation spectrum of the Sr2ZnGe2O7:Mn2+ was found to contain two excitation bands in the ultraviolet (UV) region. When excited by UV light, the sample shows bright green emission at 535 nm, which corresponds to the distinctive transition of Mn2+ (4T1→6A1). Moreover, the quantum efficiency of Sr2ZnGe2O7:Mn2+ could reach 67.6%. Finally, a high‐performance white‐light‐emitting diode (WLED) with a low correlated colour temperature of 4632 K and a high colour rendering index (CRI) of 92.3 were packaged by coating commercial blue and red phosphors with an optimized Sr2ZnGe2O7:Mn2+ sample on a 310 nm UV chip. This indicated that Sr2ZnGe2O7:Mn2+ has the potential application as a green component in the WLED lighting field. [ABSTRACT FROM AUTHOR]

Atomically thin two-dimensional (2D) bismuth oxychalcogenides have been considered as promising candidates for high-speed and low-power photoelectronic devices due to their high charge carrier mobility and excellent environmental stability. However, the photoelectric performance of their bulk materials still falls short of expectations. Herein, a novel Bi9O7.5S6/SnS composite film with a type-II heterojunction was successfully prepared by combining hydrothermal and knife-coating techniques. The crystal structure, morphology, and optical properties were systematically investigated. Under 1 V bias voltage, the photocurrent of the Bi9O7.5S6/SnS composite film can be obtained as 107 μA cm−2, which is about 29.9 times and 93.9 times higher than that of bare Bi9O7.5S6 and SnS, respectively. The type-II heterojunction has played a significant role in improving the photoelectric performance of the Bi9O7.5S6/SnS composite film by facilitating the separation and transfer of photo-generated carriers. This work sheds light on the design and development of new bismuth-based composite materials for advanced photoelectric and photocatalytic applications. [ABSTRACT FROM AUTHOR]