Synthesis And Luminescence Properties Of Mn⁴⁺and Eu³⁺co-doped Ca₃Al₄ZnO₁₀ Phosphors And Its Application

Agricultural films and agricultural lighting LEDs are important means of production.The addition of suitable light conversion agents to agricultural films can greatly improve the utilization efficiency of sunlight,increase yields,and even regulate crop growth.The wavelength range of sunlight on the earth’s surface is 280～3000 nm,but not all wavelengths of sunlight can be used by plants.Some higher-energy light can neither promote plant growth,but also is harmful to plants and agricultural plastic films.On the premise of fully preserving the basic characteristics and properties of ordinary agricultural membranes,the solar light conversion technology can convert ultraviolet（UV）light into blue,red and far red light needed by plant growth,thereby improving the comprehensive utilization of light energy and promoting crop production and precocious.This technology is receiving more and more attention from many countries.In order to obtain a light conversion materials suitable for plant growth.Mn⁴⁺,Eu³⁺ions were selected as the activator and Ca₃Al₄ZnO₁₀ as the matrix material in this work to conduct the following research:1.Firstly,the light conversion agent Ca₃Al₄ZnO₁₀:Mn⁴⁺that absorbs UV-light and emits far-red light was synthesized by high temperature solid phase reaction,and phase and luminescence properties were analyzed.The results show that the target phosphor has been successfully synthesized by the present method.Under the excitation of UV-light,Ca₃Al₄ZnO₁₀:Mn⁴⁺exhibits a far-red light emission band in the range of670-750 nm with a peak at 715 nm.Then the Ca₃Al_4-mGa_mZnO₁₀:Mn⁴⁺phosphor was synthesized,it was found that the introduction of Ga³⁺ions can increase the luminescence efficiency of Mn⁴⁺ions,and its structure characterization and luminescence properties were analyzed.2.A series of Ca₃Al₄ZnO₁₀:Eu³⁺sunlight conversion materails were synthesized by high temperature solid phase reaction method,which can absorb UV-light and emit red light.The structure and luminescence properties of them are characterized.The results show that under the excitation of UV-light,the emission band in the range of 600～640 nm,and the maximum emission peak at 615 nm.Then,Ca₃Al_4-mGa_mZnO₁₀:Eu³⁺phosphor was synthesized,and the structure and luminescence properties were characterized.It was found that the introduction of Ga³⁺can also improve the luminescence efficiency of Eu³⁺,effectively.Then,Ca₃Al_3.0Ga_1.0ZnO₁₀:Mn⁴⁺,Eu³⁺phosphors were synthesized.The structure characterization and luminescence properties analysis showed that Mn⁴⁺and Eu³⁺co-luminous as independent luminescence centers,respectively.Ca₃Al_3.0Ga_1.0ZnO₁₀:Mn⁴⁺,Eu³⁺phosphors are a dual-emission phosphor that absorbs UV-light and emits red light and far-red light,Besides,we can adjust the relative emission intensity of red light and far-red light to an extent,which has an application prospects in regulating plant growth.3.A series of Ca₃Al_3.995Ga_1.0ZnO₁₀:0.005Mn⁴⁺phosphors were synthesized by microwave radiation method,and compared with the traditional high-temperature solid-phase method in terms of phase and luminescence properties.The results show that the phase of the sample synthesized by the microwave radiation method is impure,and the luminescence efficiency is lower than that obtained by solid-phase method.