Environmental Stable Lead Halide Cesium Nanocomposite Preparation And Its Application In Plant Lighting And Backlight Display

All-inorganic lead cesium halide(CsPbX3,X=Cl,Br,I)perovskite nanocrystals(PeNCs)have broad application prospects in light-emitting diodes(LED),solar cells,lasers and other fields due to their unique photoelectric properties,such as high photoluminescence quantum yields(PLQY),narrow spectral bandwidth,wide color gamut,tunable emission wavelength and band gap.As a new type of semiconductor material,it still faces some challenges in practical applications.The instability of PeNCs is one of the important reason restricting its commercial development.In addition,the presence of heavy metal lead ions is harmful to the environment and physical health.In this thesis,a series of manganese(Mn)-doped CsPbCl3 PeNCs glass were successfully prepared by using the high temperature melting and in-situ crystallization method,and the full-spectrum CsPbX3(X=Cl,Br,I)PeNCs polymer film composite materials were successfully fabricated by traditional hot-injection method.The microstructure,stability and photoelectric properties of the samples are analyzed in details through a series of characterization methods.The research contents are mainly concluded as follows:(1)A series of Mn-doped CsPbCl3 PeNCs glass with red-blue dual-color emission at different doping concentrations were prepared by high temperature melting and in-situ crystallization method,the composition and structure were discussed in details.Benefiting from the robust glass protection,the stability of PeNCs were improve,and the doping of Mn2+ ions can replace part of the Pb2+ ions to reduce its toxicity.The light-emitting diode(LED)device constructed by matching the prepared PeNCs glass and purple light chips are used for indoor plant lighting,and the prepared device has blue-red dual-color emission,which meets the demand of light wave band for plant growth.The cabbages were cultivated under indoor conditions for 28 days,and the commercial white light emitting diode(WLED)were selected as a comparison.The results showed that the average growth height of cabbages irradiated with perovskite LED was about 1.4 cm higher than that under WLED irradiation.In addition,The temperature-dependent photoluminescence(PL)spectrum of Mn2+ions exhibited an abnormal phenomenon,which can be further studied in the field of temperature sensor.(2)To improve the stability of PeNCs,polymer matrix was utilized to protect them,and a full-spectrum CsPbX3@SEBS composite material with high PLQY was prepared.The flexible film exhibits excellent water resistance and thermal stability.The constructed LED based on CsPbX3@SEBS film,which expanded its application in backlight display.In addition,the CsPbBr3@SEBS with green light emission and the red-emission CsPbBrI2@SEBS composite film are coupled with the InGaN blue chip to construct a WLED with a color coordinate of(0.3269,0.3211),which has broad application prospects in next-generation solid-state lighting and display devices.