Halide perovskite has been widely studied as a new generation of photoelectronic materials. However, their thermal and humidity-induced emission quenching have greatly limited their utility and reliability. Here, we report a hexagonal Mn 2 + -doped CsCdCl 3 perovskite crystal that possesses stable photoluminescence (PL) at both high temperature and humidity. The room temperature long-persistent luminescence (LPL) of the single crystals lasts up to 1480 s and can be adjusted by changing the concentration of Mn 2 + ion doping. The characteristic emission of d-d transition of Mn 2 + is realized, and the photoluminescence quantum yield (PLQY) is up to 91.4 %, it can maintain more than 90 % of the initial PL spectral integral area at 150 °C (423 K). High humid stability PL can be achieved more than 75 % of the initial PL intensity after 55 days of immersion in water. These excellent properties show the application prospect of the LPL material in lighting indication and anti-counterfeiting.

In previous work, the photocatalytic stability during the recycled degradation is employed to evaluate the inhibitory effect of photocorrosion. Then, a significant question arises: is the photocatalytic stability only related to the photocorrosion for ZnO? The answer turns out to be no in our work. The phenomenon of photocatalytic reaction-induced selective corrosion of ZnO nanosheets was firstly revealed. It is found that the special corrosion not only needs UV light irradiation, but also results from the photocatalytic reaction. Then, the impacts of this special corrosion and photocorrosion on morphology and photocatalytic stability were compared. It is found that the PRIS corrosion shows more mass loss, more selective etching and more decrease of unit mass photocatalytic activity than that of photocorrosion. The results indicate that the special corrosion-induced active face loss rather than the photocorrosion-induced mass loss can be fatal for the photocatalytic stability. Accordingly, a direct and visual confirmation of inhibitory effect of loaded Ag against selective corrosion is revealed.

The long persistent luminescence (PersL) and color adjustable properties in high‐temperature environment are of great significance for luminescent materials in the fields of multiple anti‐counterfeiting, biological imaging, and optical temperature sensing (OTS). In this work, a series of self‐activated CaNb2O6 (CNO): Tb3+ phosphors have been successfully synthesized by solid‐state reaction route, the OTS, and temperature‐dependent PersL of these phosphors is carried out and investigated in detail. Relying on the energy transfer from host to the activator Tb3+ ion, the visual color‐tunable emissions from blue to green were detected with the increase of temperature and the maximum absolute and relative sensitivities reach 0.955% K‐1 and 1.243% K‐1. Moreover, the temperature‐dependent PersL characteristics were investigated systematically, and the initial brightness and the lasting time all reach a maximum value at 323 K in the representative CNO: 1%Tb3+ sample. All the results show that the high‐temperature persistent phosphor has potential applications in OTS and anti‐counterfeiting field.

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The design and characterization of a novel color tunable long persistent composite phosphor through radiative energy transfer.

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In thiswork, we investigate the influence of Mn 2+ on the emission color, thermal sensing and optical heater behavior of NaGdF 4 : Yb/Er nanophosphors, which the nanoparticles were synthesized by a hydrothermal method using oleic acid as both a stabilizing and a chelating agent. The morphology and crystal size of upconversion nano particles (UCNPs) can be effectively controlled through the addition of Mn 2+ dopant contents in NaGdF 4 : Yb/Er system. Moreover, an enhancement in overall UCL spectra of Mn 2+ doped UCNPs for NaGdF 4 host compared to the UCNPs is observed, which results from a closed back-energy transfer between Er 3+ and Mn 2+ ions ( 4 S 3/2 (Er 3+ ) → 4 T 1 (Mn 2+ ) → 4 F 9/2 (Er 3+ )). The temperature sensitivity of NaGdF 4 :Yb 3+ /Er 3+ doping with Mn 2+ based on thermally coupled levels ( 2 H 11/2 and 4 S 3/2 ) of Er 3+ is similar to that particles without Mn 2+ in the 303–548 K range. And the maximum sensitivity is 0.0043 K −1 at 523 K for NaGdF 4 :Yb 3+ /Er 3+ /Mn 2+ . Interestingly, the NaGdF 4 :Yb 3+ /Er 3+ /Mn 2+ shows preferable optical heating behavior, which is reaching a large value of 50 K. These results indicate that inducing of Mn 2+ ions in NaGdF 4 :Yb 3+ /Er 3+ nanophosphors has potential in colorful display, temperature sensor.

Micro-sized Gd6O5F8 particles doped with Yb3+, Ho3+ and Li+ ions have been synthesized by a facile hydrothermal route.