Study On Fluorescence Properties Of Gd³⁺/Er³⁺/Yb³⁺ Doped Upconversion Oxide Materials

Up-conversion fluorescent materials have potential applications in the fields of biosensors,lasers,and high-resolution displays.However,the low conversion efficiency of up-converting fluorescent materials is the main obstacle restricting its development.Improving the fluorescence conversion efficiency of up-conversion materials has always been a research hotspot.Introducing sensitizer ions is a way to solve this problem.Through literature research,it is found that Gd³⁺ions show good sensitization in some fluorescent systems,which can improve the up-conversion luminous efficiency of activated ions.It is of great research significance to study the sensitization mechanism of Gd³⁺ions in the up-conversion system and expand its application.Therefore,we selected rare earth oxides with high physical stability and chemical durability,and lower phonon energy as the matrix.In the Yb³⁺/E³⁺co-doped system,doped with Gd³⁺ions,study its up-conversion luminescence and temperature sensing characteristics,and analyze the sensitization effect of Gd³⁺ions.We prepared Y₂O₃,Lu₂O₃and La₂O₃phosphors co-doped with Yb³⁺,Er³⁺and Gd³⁺ions by the sol-gel method,and studied the up-conversion luminescence mechanism and temperature sensing characteristics by doping Gd³⁺ions with different concentrations.Under the excitation of 980 nm laser,the Y₂O₃and Lu₂O₃samples radiate bright green and red light,and weak ultraviolet light.Studies have shown that the introduction of Gd³⁺ions causes distortion of the lattice field of the material and enhances the up-conversion luminescence intensity of Er³⁺ions in the visible region.In the ultraviolet region,the 313 nm radiation peak of Gd³⁺ion ⁶P_7/2?⁸S_7/2was measured.Fluorescence intensity ratio method was used to study the optical temperature sensing characteristics of ²H_11/2and ⁴S_3/2based on Er³⁺ions in the range of 313-573 K.The highest temperature sensitivity is obtained when the concentration of Gd³⁺ions is 10 mol%.For La₂O₃phosphor,the sample emits bright green and red light under the excitation of 980 nm laser,and the radiation peak??807 nm?of Er³⁺ion ⁴I_9/2?⁴I_15/2transition is observed.Using the fluorescence intensity ratio method,the optical temperature sensing characteristics of Er³⁺ion ²H_11/2and ⁴S_3/2thermal coupling energy levels in the range of 313-573 K were studied.The study showed that the doping of Gd³⁺ions did not improve the sample measurement Temperature sensitivity.