Luminescence Properties Research Of Ce³⁺/Eu²⁺/Mn²⁺Co-doped Ca₉Ln?PO₄?₇?Ln=La,Lu,Gd? Single-phase White Light Emission Phosphors Prepared By Topochemical Reduction Reaction

White light emitting diodes?WLEDs?have been hailed as the next generation lighting source due to their high efficiency,energy saving,and environmental protection.The UV-LED chip is used to excite the single-phase white light emitting phosphor that integrates the red,green,and blue colors in a single-phase host material,which can prevent the UV-LED chip from being strongly absorbed by the blue light when the red,green,and blue colors are excited.Causes a problem of low transmission efficiency.Due to the complex interaction of energy transfer between energy donors and energy acceptors,when co-doping light-emitting ions into a single-phase white light emitting phosphor,the quantum efficiency of the phosphor decreases sharply.Topochemical reduction reaction uses a mild chemical synthesis route to design the required metastable phase and then generates the structure and composition of the metastable phase.In this thesis,the single-phase white light emitting phosphors doped with rare earth ions doped with phosphorescent systems have the problems of low luminous intensity and low luminous efficiency after modification.By introducing a localized reaction strategy,the single-phase white light emitting phosphors have been illuminated.Optimization of performance.The main research contents are as follows:?1?Luminescence performance of Ca₉Ln?PO₄?₇:Eu²⁺?Ln = La,Lu,Gd?phosphors was regulated by topochemical reduction reaction.First,the Ca₉Ln?PO₄?₇:Eu²⁺ precursor?Ln = La,Lu,Gd?was prepared by the traditional high-temperature solid-phase method,and its basic luminescence properties were studied by a fluorescence spectrometer.?2?Luminescence performance of Ca₉Ln?PO₄?₇:Eu²⁺ Mn²⁺?Ln = La,Lu,Gd?phosphors was regulated by topochemical reduction reaction.First,the Ca₉Ln?PO₄?₇:Eu²⁺ Mn²⁺ precursor?Ln = La,Lu,Gd?was prepared by the traditional high-temperature solid-phase method,and its basic luminescence properties were studied by a fluorescence spectrometer.Through topochemical reduction reaction to adjust its optical properties such as luminous intensity,quantum efficiency,attenuation,etc.,XRD,DC and other characterization methods are used to study the structure of the luminescent material and the energy transfer between ions.The mechanism for greatly optimizing the phosphor luminescence performance and PLQY are discussed and studied.?3?Ca₉Ln?PO₄?₇:Ce³⁺ Eu²⁺ Mn²⁺?Ln = La,Lu,Gd?phosphors were regulated by a topochemical reaction method.XRD,fluorescence spectrometer and other methods were used to characterize the phase structure and luminescence properties of Ca₉Ln?PO₄?₇:Ce³⁺ Eu²⁺ Mn²⁺?Ln = La,Lu,Gd?phosphors;different concentrations of multi-doped rare earth ions Optimize to find the optimal doping concentration to maximize the spectral range.At the same time,XRD,PL and other characterization methods were used to study the structural changes of the treated Ca₉Ln?PO₄?₇:Ce³⁺ Eu²⁺ Mn²⁺?Ln = La,Lu,Gd?phosphors.