Enhanced luminescence performances of Mn4+-activated Sr4Al14O25 red phosphors by doping with Sc3+ ions

High performance Sr4Al14O25:Mn4+ phosphor: structure calculation and optical properties

“…[35][36][37] These bands are all assigned to the bending vibration of the O-Al-O bonds and stretching vibration of Al-O bonds in the co-angular tetrahedron. 38 Combined with the crystal structure scheme of Fig. 1a and e The conclusion is consistent with that of XRD analyses.…”

“…35–37 These bands are all assigned to the bending vibration of the O–Al–O bonds and stretching vibration of Al–O bonds in the co-angular tetrahedron. 38 Combined with the crystal structure scheme of Fig. 1a and e, only [AlO 4 ] units without [AlO 6 ] units are found in SrAl 2 O 4 and the converse (co-existence) lie in Sr 4 Al 14 O 25 .…”

“…7b, which corresponds to the 2 E g - 4 A 2g transition of Mn 4+ . 38 With increasing sintering temperature from 1200 to 1450 °C, the intensity of PL and PLE increase firstly and then decrease. SAO-1250 exhibits the maximal value, which is owing to superior crystallinity of Sr 4 Al 14 O 25 .…”

“…Generally, there are three types of AlO 6 octahedra (Al(1)O 6 , Al(2)O 6 and Al(3)O 6 ) in the structure of Sr 4 Al 14 O 25 . 6,22,38 Doping Mn 4+ into the structure, Mn 4+ prefers to occupies two lattice sites of Al(1) and Al(2) and the remaining Al(3) site does not contribute. 39 Therefore, the decay lifetime of SAO:Mn 4+ should exhibit a double exponential curve and be fitted by the following formula:where A 1 , A 2 is fitting constants, τ 1 , τ 2 is exponential components, I is luminescence intensity and t is time.…”

Tremendous Acceleration of Plant Growth by Applying a New Sunlight Converter Sr4Al14−xGaxO25:Mn4+ Breaking Parity Forbidden Transition

“…In general, sunlight plays a vital role in plant growth, and three specific wavelengths of light are particularly important for plant growth: blue light (400–500 nm), red light (620–690 nm), and near‐infrared color (730–760 nm), which are responsible for phototropism, [ 1 ] photosynthesis, [ 2 ] and photomorphogenesis, [ 3 ] respectively. Among them, photosynthesis is a necessary condition for plant growth, so enhancing the light intensity in the red band can effectively enhance the photosynthesis of plants.…”