POE enhanced stabilities of CsPbX_(3)(X=Br,Ⅰ)perovskite and their white LED application

Perovskite has received extensive attention due to its excellent properties, just like photoelectric, while the instability has always troubled us to the wide application of perovskite materials. Herein, we proposed to use SiO_(2)and POE to encapsulate perovskite nanocrystals(PNCs). In this work, we have successfully prepared a series of perovskite composite materials and films with different concentration ratios.Due to the protection of POE, the luminous intensity of CsPbBr_(3)@POE composite film remained above 90% after stayed in the water for 42 days. The lead concentration of CsPbBr_(3)@POE composite film was 0.8 μg/m L after 48 h of immersing in deionized water. Namely, packaging PNCs in POE could effectively prevent Pb from overflowing reduce Pb pollution. Besides, the composite films showed a wide colour gamut with 117% of NTSC colour gamut, which shows that this composite material has a development prospect in the WLED field.

Enhanced multimodal luminescence and ultrahigh stability Eu^(3+)-doped CsPbBr_(3) glasses for X-ray detection and imaging

As an emerging scintillation material,metal halide perovskite(CsPbX3)has been deemed the most potentially valuable candidate in X-ray detection and medical imaging.Nevertheless,it is a continuing challenge to implement efficient radioluminescence(RL)with high radiation stability and moisture resistance.Moreover,the optimized luminescence properties and excellent uniformity of CsPbX3 glass are also key points for obtaining perfect X-ray images.Herein,we have successfully precipitated Eu^(3+)-doped CsPbBr_(3)nanocrystals(NCs)with improved photoluminescence quantum yield(≈58.6%)because partial Eu^(3+)entered the perovskite lattice in a robust borosilicate glass matrix by in situ crystallization.The small amount of Eu addition made the lattice of NCs shrink and promoted uniform distribution of CsPbBr_(3)NCs in the glass,which effectively reduced the light scattering of the sample.Subsequently,multimodal RL intensity of the CsPbBr_(3)/CsPbBr_(3):xEu NCs glasses(CPB-0Eu/CPB-xEu)as a function of X-ray dose rate showed a superlinear relationship to the benefit of obtaining satisfactory X-ray images.Also,the outstanding radiation stability and water resistance of CPB-xEu were confirmed due to the protection of the robust glass matrix.Finally,an X-ray imaging system using a CPB-xEu scintillator was constructed,and the spring in the opaque sample was legibly detected under the motivation of X-rays,indicating that CsPbX3 glasses possess extensive application prospects in terms of X-ray detection and medical imaging.

Ultrastable Gd^(3+)doped CsPbCl_(1.5)Br_(1.5) nanocrystals blue glass for regulated and low thresholds amplified spontaneous emission

Here,Gd-doped CsPbCl_(1.5)Br_(1.5) nanocrystals(NCs)in borosilicate glass matrix(B_(2)O_(3)−SiO_(2)−ZnO)were prepared by melting quenching and in-situ crystallization.The optical performance of CsPbCl_(1.5)Br_(1.5) NCs glasses under different heat-treatment temperatures and the content of Gd^(3+) were analyzed in detail.After CsPbCl_(1.5)Br_(1.5) NCs glass is doped with Gd^(3+)ions,the photoluminescence intensity increases and the synthesized Gd-doped CsPbCl_(1.5)Br_(1.5) NCs glasses have excellent water stability and thermal cycling performance.In addition,the influence of Gd-doped concentrations and heat-treatment temperatures on the amplified spontaneous emission(ASE)thresholds of CsPbCl_(1.5)Br_(1.5) NCs glasses was studied,and the Gd-doped CsPbCl_(1.5)Br_(1.5) NCs glasses achieve controllable ASE thresholds at room temperature.The ASE threshold can be as low as 0.39 mJ∕cm^(2).This work offers a neoteric reference for the research in the application of metal ion-doped perovskite NCs and a new idea for the realization of controllable and low ASE thresholds on perovskite NCs.