Research progress and application prospects of transition metal Mn⁴⁺-activated luminescent materials

Abstract

Transition metal Mn4+doped materials showing very narrow red emission have attracted tremendous interest for compositions based on abundant resources and mild production processes.

LaAlO3:Mn4+ as Near-Infrared Emitting Persistent Luminescence Phosphor for Medical Imaging: A Charge Compensation Study

“…The crystal field splitting creates a large gap between the t 2g and e g states, stabilizing the 4+ oxidation state [21,40,41]. Therefore, Mn 4+ ions are usually found on octahedral sites of solids [40,41]. For Ge 4+ and Ti 4+ , they also have a stable chemical environment like the Mn 4+ ion, so we adopted these ions as co-dopants.…”

Photoluminescence Properties of Layered Perovskite-Type Strontium Scandium Oxyfluoride Activated With Mn4+

“…Interestingly, the emission from Sr 2 ScO 3 F:Mn was much stronger than that from Sr 2 TiO 4 :Mn; the internal and external quantum yields of Sr 2 ScO 3 F:Mn excited at 345 nm at room temperature (50.5 and 43.5%) were much higher than those of Sr 2 TiO 4 :Mn excited at 380 nm (3.4 and 2.5%). The Mn 4+ -emission from fluoride hosts consists of some very sharp lines while that from oxide hosts is broad (Zhou et al, 2016; Adachi, 2018). The emission from Sr 2 ScO 3 F:Mn is broad as well as Mn 4+ -activated oxide phosphors despite presence of the Sc-F bond.…”

“…Therefore, development of alternative yellow—to red-emitting phosphors activated with Eu 2+ , which can be synthesized milder conditions in comparison with nitrides, is also conducted for oxides, phosphates, and oxyhalides (Toda et al, 2006; Daicho et al, 2012, 2018; Kim et al, 2013; Sato et al, 2014; Wen et al, 2016). Besides, phosphors activated with Mn 4+ have been recently paid attention due to capability of red emission using wide variety of host materials (Srivastava and Beers, 1996; Seki et al, 2013; Ye et al, 2013; Sasaki et al, 2014; Wang et al, 2014; Takeda et al, 2015, 2017; Zhou et al, 2016; Cai et al, 2017; Wu et al, 2017; Xi et al, 2017; Zhang et al, 2017; Adachi, 2018; Jansen et al, 2018). Octahedral 6-fold coordination sites are preferred for substitution of Mn 4+ ions.…”

Tunable dual‐mode emission with excellent thermal stability in Ca4ZrGe3O12:Eu phosphors prepared in air for NUV‐LEDs

“…However, because of the deficient of red component, this kind of W‐LEDs suffers from high correlated color temperature and low color rendering index. To overcome this scarcity, a strategy of the integration of near‐ultraviolet (NUV) LEDs with RGB (red, green, and blue) tricolor phosphors has been developed . Nevertheless, the thermal quenching effect of phosphors seriously restricts their practical utilizations in W‐LEDs, particularly in high power situations or laser LEDs.…”