Aqueous-Based Inorganic Colloidal Halide Perovskites Customizing Liquid Scintillators.

Compared to solid scintillators and organic liquid scintillators, aqueous-based liquid scintillators (AbLS) have more superiority in highly flexible scalability, yet are now limited by their low light yield (≈100 photons MeV-1 ). Here, aqueous-based inorganic colloidal halide perovskites with high photoluminescence quantum yield (PLQY) of three primary color luminescence up to 88.1% (red), 96% (green), and 81.8% (blue) are respectively synthesized, and a new generation of colloidal perovskite-mediated AbLS (PAbLS) with light yield increased in comparison with the commercial scintillator AbLS is fabricated. This paper exhibits that the excellent PLQY and colloidal dispersion of halide perovskites benefit from poly(ethylene glycol) modification and this modification ensures the vacancy inhibition and formation of defect-free surfaces in an aqueous solution. Moreover, their high luminescent emission can be maintained for 100 days at low temperatures, and such modification also promises the heat-to-cold customization of operating temperature even in ice below 0 °C. Finally, depending on the light yield of around 3058 and 8037 photons MeV-1 at room temperature and low temperature, PAbLS with shape/size scalability exhibit their robust radiation hardness (dose rate as high as 23 mGy s-1 ) and conceptual application potential in high-energy ray radiation detection from every angle of 360°.

Highly Thermotolerant Metal Halide Perovskite Solids.

By virtue of their narrow emission bands, near-unity quantum yield, and low fabrication cost, metal halide perovskites hold great promise in numerous aspects of optoelectronic applications, including solid-state lighting, lasing, and displays. Despite such promise, the poor temperature tolerance and suboptimal quantum yield of the existing metal halide perovskites in their solid state have severely limited their practical applications. Here, a straightforward heterogeneous interfacial method to develop superior thermotolerant and highly emissive solid-state metal halide perovskites is reported and their use as long-lasting high-temperature and high-input-power durable solid-state light-emitting diodes is illustrated. It is found that the resultant materials can well maintain their superior quantum efficiency after heating at a temperature over 150 °C for up to 22 h. A white light-emitting diode (w-LED) constructed from the metal halide perovskite solid exhibits superior temperature sustainable lifetime over 1100 h. The w-LED also displays a highly durable high-power-driving capability, and its working current can go up to 300 mA. It is believed that such highly thermotolerant metal halide perovskites will unleash the possibility of a wide variety of high-power and high-temperature solid-state lighting, lasing, and display devices that have been limited by existing methods.

La2O2CO3:Tb3+ one-dimensional nanorod with green persistent luminescence.

Trivalent terbium-doped oxycarbonate (La2O2CO3:1%Tb3+) one-dimensional nanorods are synthesized via a facile precipitation method. The average length of La2O2CO3:1%Tb3+ nanorods is 184.5 nm. Doping Tb3+ ions led to several visible emission peaks at 486 nm, 542 nm, and 587 nm under excitation of 258 nm wavelength light. The green afterglow at 542 nm can be detected almost 600 s after ceasing the UV-light irradiation. It can be calculated that the La2O2CO3:1%Tb3+ sample has one shallow trap depth (E = 0.848 eV) by measuring the thermoluminescence. All the results indicate that a simple precipitation method can synthesize a one-dimensional nanorod with green persistent luminescence.