The Optical And Temperature-depent Stability Properties Of Ternary Semiconductor Nanocrystals

Cesium lead halide?CsPbX₃?X=Cl,I,Br??perovskite nanocrystals?NCs?have revealed brilliant prospect in lighting,display and lasing fields owing to their excellent photoluminescence properties.On the one hand,the subsistent major disadvantage for the CsPbX₃ perovskite NCs is lack of cofluorescence because of their superior monochromaticity.However,although the emitted spectrum can cover the entire range by the adjustment of the halogen,the exchange between the halogens is extremely easy and it is impossible to to obtain a composite light by simply mixture.On the other hand,the most mature synthesis method of perovskite NCs is hot-injection,which is cumbersome,time consuming.What's more,poor stability of perovskite NCs due to sensitivity to substances such as water and oxygen.In addition,environmentally unfriendly atoms Pb are also need to be excluded.In order to solve the above problems,the following work was carried out;?1?To dope rare earth ions into halide perovskite,CsPbX₃?X=Cl,Br,I?NCs hosts not only inherit the excellent narrow linewidth excitonic properties but also yield unique photoluminescence emission.The single doped-NCs present wide color gamut emission covering whole visible spectrum.A noticeable spin-polarized ⁵D₀?⁷F_1-6 emission of Eu³⁺ions is acquired owing to energy transfer from excitons to dopants.Moreover,the energy transfer is temperature-dependent which originating from the increase of nonradiative transition probability,leading to decrease for the NCs hosts'PL intensity,but increase for the PL intensity of dopants.?2?CsPbBr₃ NCs are acquired by microwave-assisted method without insert atmosphere at room temperature.Moreover,the stability of NCs is improved owing to the encapsulant of dimethicone to form CsPb?Br/Cl?₃:Mn²⁺@Dimethicone?CPBCMD?structure and extend the emission specture.Light stability increased by 10%and thermal stability increased by approximately 7%.?3?CdIn₂S₄,ZnIn₂S₄,CdGa₂S₄,ZnGa₂S₄ NCs were prepared by hot-injection method and the emission light all in blue range.In order to broaden its emission spectrum,Mn²⁺was doped into CdIn₂S₄ and the emission light cove from blue to orange.In addition,the absorption peak of Mn-doped CdIn₂S₄ NCs moved toward the long wavelength gradually with the reaction time increase.