Study On The Photoluminescence Properties Of Mn⁴⁺-Activated Phosphors Based On Topo-Chemical Reduction Method

White light-emitting diodes?WLEDs?are regarded as the next generation of lighting sources due to their advantages of high efficiency,energy saving and environmental protection.Red phosphor is the key material for WLEDs to achieve high color rendering and warm white light emission.Non-rare-earth matrix red phosphors activated by Mn⁴⁺ions have attracted wide attention from academia and industry due to their low cost of raw materials,simple synthesis and good spectral properties.In this paper,in order to solve the problems of low luminescence intensity of fluoride red phosphors activated by Mn⁴⁺ions after modification and low luminescence efficiency of oxide red phosphors activated by Mn⁴⁺ions,the photoluminescence performance of red phosphors was optimized by introducing low temperature topo-chemical reduction strategy.The main research contents are as follows:?1?The luminescent properties of K₂TiF₆:Mn⁴⁺phosphors coated with TiO₂ were regulated by low temperature topo-chemical reduction reaction.Firstly,K₂TiF₆:Mn⁴⁺phosphors coated with TiO₂ were prepared by co-precipitation method,and their basic luminescent properties were studied by fluorescence spectrometer.The luminescent intensity and thermal stability of phosphors were controlled by low temperature topo-chemical reduction reaction.The structure and morphology of phosphors were characterized by XRD and SEM.The mechanism of enhancing luminescent intensity of phosphors by low temperature topo-chemical reduction reaction was discussed and studied.?2?Sr₃WO₆:Mn⁴⁺red phosphors with composite perovskite structure were prepared by solid-state reaction method.The phase structure and photoluminescence properties of Sr₃WO₆:Mn⁴⁺phosphors were characterized by XRD and fluorescence spectrometer,and the luminescence intensity of Sr₃WO₆:Mn⁴⁺phosphors was enhanced by charge compensation method.The prepared Sr₃WO₆:Mn⁴⁺red phosphors were further modified by low temperature topo-chemical reduction method,and the structural changes of the treated Sr₃WO₆:Mn⁴⁺phosphors was investigated by XRD,XPS,Raman and other characterization methods.The mechanism of improving the luminescence properties of phosphors by low temperature topo-chemical reduction reaction was analyzed and discussed.