Views:264 Author:Site Editor Publish Time: 2020-04-05 Origin:Site
Persistence luminous materials is a kind of photoluminescent material. It is a kind of material that absorbs energy and can continue to emit light after excitation stops. As one of the earliest materials for research and application, does everyone know what materials persistence luminous materials have?
Silicate-based persistence luminous materials have attracted more and more attention in recent years due to their good chemical stability and thermal stability, as well as cheap and readily available raw material silicon dioxide, silicate-based persistence luminous materials are widely used in lighting and display fields as a kind of self-luminous material. Since 1975, Japan first developed silicate-based persistence luminous materials Zn2SiO4:Mn,As, and the rest glow time is 30min.
Since then, various silicate-based persistence luminous materials have been developed one after another, such as Sr2MgSi2O7:Eu,Dy, Ca2MgSi2O7:Eu,Dy, MgSiO3:Mn,Eu,Dy. The main activator in Silicate-based persistence luminous materials is Eu2+, and its luminescent color is still concentrated in blue-green light, although red Silicate-based persistence luminous materials are also reported. Eu and Dy co-doped Sr2MgSi2O7 and Ca2MgSi2O7 have better afterglow performance, which rest glow duration is more than 20h. In addition, red long afterglow was observed in MgSiO3 co-doped with Mn, Eu and Dy. Silicate-based persistence luminous materials have incomparable advantages over aluminate system in water resistance, but its performance is worse than aluminate.
Since 1993, Matsuzawa synthesized Dy-co-doped SrAl2O4: EU, research found that the rest of the glow decay time was as long as 2000min. Subsequently, people have successively developed a series of rare earth activated aluminate persistence luminous materials, such as blue CaAl2O4:Eu, Nd and cyan Sr4Al14O25:Eu, Dy. The activator of aluminate persistence luminous materials is mainly Eu, and the afterglow emission color is mainly concentrated in the blue-green wavelength range. Up to now, although the water resistance of aluminate is not very good, the aluminate system persistence luminous materials SrAl2O4:Eu, Dy and Sr4Al14O25:Eu, Dy have still obtained great commercial application, and they are the main research and application focus materials of long afterglow materials at this stage as a important material to make self-luminous product.
In addition to the above-mentioned major types of persistence luminous materials, sulfide which called ZnS: Cu, Co and CaS: Eu, Tm are the representatives of the persistence luminous materials, which are characterized by various colors. But the maximum initial brightness of the rest glow is only about 40mcd/m, and in the first few minutes of this kind of materials, the afterglow brightness drops sharply and the effective afterglow time is very short. There are also titanates CaTiO3: Pr, Al. persistence luminous which included Pr has been extensively studied in oxidation systems. It is worth noting that there are also persistence luminous phenomena in chlorine-containing oxides Ca8Zn (SiO4) 4Cl2: EU and nitrides Ca2Si5N8:Eu.
In any case, with the rapid development of new materials, consumers will prefer safe, hygienic and effective new energy supplies. For example, if you want to buy luminous product, the one which made by inorganic self-luminous material will be chosen for its function including light storage and self-luminous.