Study On Preparation And Spec-tral Characteristics Of Mn Ion Doped Poly-aluminate

In today’s society,due to the gradual scarcity of the earth’s energy,with the development of science and technology,all countries in the world consume more and more energy.Nowadays,countries all over the world are looking for and developing new energy sources,such as nuclear power generation,wind power generation,hydropower generation,etc.,but thermal power generation is still the main source of electricity for all countries.According to statistics in 2019,my country’s hydroelectric power generation accounted for about 16%of the country’s total power generation,wind power generation accounted for about 5%,nuclear power generation accounted for about 5%,solar power generation accounted for about 2%,and thermal power Power generation accounts for 72%of the country’s total power generation.As the earth’s resources continue to decrease,countries in the world including our country must not find ways to save energy consumption.The power consumption of lighting occupies a large proportion of the power consumption of our lives.As a fourth-generation new light source,LED is expected to completely replace incandescent lamps due to its high luminous efficiency,long service life,low energy consumption,and environmental protection.Fluorescent lamps have become the main source of lighting in our lives.Today LEDs have been used in various fields.In recent years,Mn4+doped red luminescent materials have become one of the hottest research topics in the field of luminescent materials due to their low synthesis cost,simple preparation process and narrow emission band.In this thesis,two polyaluminates,Ba₂Al₁₀O₁₇and Sr Mg Al₁₀O₁₇,were selected as the matrix doped into Mn⁴⁺ions,and Ba₂Al₁₀O₁₇:Mn⁴⁺fluorescent materials and Sr Mg Al₁₀O₁₇:Mn⁴⁺fluorescent materials were successfully prepared.By discussing and analyzing the influence factors of different Mn4+doping concentration,burning temperature and holding time,the phase crystal structure of the phosphor sample is characterized by the X-ray diffractometer,and the phosphor sample is excited by the steady-state fluorescence spectrometer.The spectrum,emission spectrum and fluorescence lifetime are analyzed,and the color coordinates of the phosphor samples are depicted by CIE1931 chromaticity coordinate software.The XRD of Ba₂Al₁₀O₁₇:Mn⁴⁺phosphors with different Mn⁴⁺doping concentrations was compared with that of the Ba₂Al₁₀O₁₇compound standard card,and it was basically the same that no obvious impurity peaks were found.Comparing the excitation and emission spectra of fluorescent material samples with different Mn4+doping concentrations,it is found that the positions of the excitation and emission peaks have not changed,and the excitation and emission intensity has changed.When the doping concentration of Mn4+is 1%,the excitation and emission intensities are Reaches the maximum value.The excitation peaks are located at300nm and 450nm,and the emission peaks are located at 660nm and 671nm.The best firing temperature for the preparation of Ba₂Al₁₀O₁₇:0.01Mn⁴⁺phosphor with 1%Mn⁴⁺doping concentration is 1400℃.The optimal holding time for the preparation of Ba₂Al₁₀O₁₇:0.01Mn⁴⁺phosphor at a fixed burning temperature of 1400℃is 3h.As the Mn⁴⁺doping concentration increases,the fluorescence lifetime decreases.The CIE color coordinate of Ba₂Al₁₀O₁₇:0.01 Mn⁴⁺phosphor is（0.7015,0.2967）,which is located in the red light region.By comparing Sr Mg Al₁₀O₁₇:Mn⁴⁺phosphors with different Mn⁴⁺doping concentrations and Sr Mg Al₁₀O₁₇compound standard cards,they are basically consistent and no obvious impurity peaks are found.Changing the Mn⁴⁺doping concentration,the position of the excitation and emission peaks of the phosphor sample did not change,and the excitation and emission intensity reached the maximum when the Mn⁴⁺doping concentration was 1%.The excitation peaks are located at 328nm,400nm and 470nm,and the emission peaks are located at 643nm,658nm and 674nm.The optimal sintering temperature of Sr Mg Al₁₀O₁₇:0.01Mn⁴⁺phosphor prepared at 1%Mn⁴⁺doping concentration is 1500℃.With the increase of Mn⁴⁺doping concentration,the fluorescence lifetime decreases.The CIE color coordinate of Sr Mg Al₁₀O₁₇:0.01Mn⁴⁺phosphor is（0.7221,0.2787）,which is located in the red light region.