The Preparation And Study Of Mn-doped Perovskite Quantum Dot Glass And Glass Fibers

All inorganic cesium lead halide?Cs Pb X₃,X=Cl,Br,I?perovskite quantum dots?QD?obtained widespread attention in recent years due to their excellent photoluminescence performance and tunable bandgap structure.As a kind of promising luminescent materials,Cs Pb X₃perovskite QDs have broad applications in optoelectronic fields,such as low-threshold lasers,high-efficiency light emitting diodes?LEDs?,photodetectors and solar cells.However,Cs Pb X₃perovskite QDs synthesized by chemical methods have poor stability.They are sensitive to the surrounding environment such as moisture,oxygen,light and heat.As a robust matrix,glass have high resistance,high strength and good stability.Therefore,we embedded Cs Pb X₃perovskite QDs in glass matrix.In this paper,CsPbCl_xBr_3-xperovskite QDs with different sizes were successfully precipitated in phosphate glass matrix under heat treatment at different temperatures.The luminescence characteristics and stability of CsPbCl_xBr_3-xperovskite QD glass were studied.On this basis,Mn²⁺doped CsPbCl_xBr_3-xperovskite QD glass with double emission peaks was successfully prepared,and the energy transfer process between CsPbCl_xBr_3-xperovskite QDs and Mn²⁺ions in the glass was studied.Finally,Mn²⁺doped CsPbCl_xBr_3-xperovskite QD glass fibers were prepared by melt-in-tube method,and its luminescence properties were studied.The main research contents are as follows:?1?Transparent CsPbCl_xBr_3-xperovskite QD precursor glass was prepared by the traditional melting-quenching method.After heat treatment at different temperatures,different sizes of CsPbCl_xBr_3-xperovskite QDs were successfully precipitated in phosphate glass.Under 365 nm excitation,blue emission of CsPbCl_xBr_3-xperovskite QDs around 470 nm can be observed.As the heat treatment temperature increases,the luminescence peak position gradually red shifts.During one heating and cooling cycle at 200°C,the emission intensity of CsPbCl_xBr_3-xperovskite QD glass can be fully recovered.After directly storing CsPbCl_xBr_3-xperovskite QDs in water and ethanol for 8 days,it can still maintain good luminescence characteristics.?2?Mn²⁺doped CsPbCl_xBr_3-xperovskite QD glass was successfully prepared by the same method.After heat treatment at 400°C for 3h,CsPbCl_xBr_3-xperovskite QD glass doped with different concentrations of Mn²⁺ions has two emissions,which are derived from the exciton recombination emission of CsPbCl_xBr_3-xQDs and the d-d transition of Mn²⁺ions,respectively.The experimental results show that there is an energy transfer process between CsPbCl_xBr_3-xQDs and Mn²⁺ions.By changing the doping concentration of Mn²⁺ions,the intensity ratio of blue light and red emission can be changed.The luminescent color changes from blue to purple and to the orange area,which is expected to be used in color converters.?3?We used Mn²⁺doped CsPbCl_xBr_3-xperovskite QD glass as the core glass,and commercial K9 glass as the cladding glass.Mn²⁺ion-doped CsPbCl_xBr_3-xperovskite QD glass fibers were rapidly drawn at 950°C by melt-in-tube method.The structural characterizations showed that the prepared precursor glass fiber core is amorphous and transparent.Through the elemental distribution analysis of the cross section of Mn²⁺doped CsPbCl_xBr_3-xperovskite QD glass fibers,it is found that there is no obvious element diffusion between the core and the cladding glass.The luminescence properties of Mn²⁺ion-doped CsPbCl_xBr_3-xperovskite QD glass fibers at different heat treatment temperatures were studied.Mn²⁺doped CsPbCl_xBr_3-xQD glass fibers for temperature sensor were explored.By measured and fitting,the fluorescence intensity ratio(FIR,I₆₄₆/I₄₆₀)has a linear relationship with 1/T and the FIR is consistent during heating and cooling process,confirmed that Mn²⁺doped CsPbCl_xBr_3-xglass fibers have good repeatability.