Weak blue light absorption severely limits the application of Mn^(2+)-activated narrowband green phosphors.Herein,a strategy to improve the absorption of Mn^(2+)-activated phosphors is proposed by selecting a suit abl...Weak blue light absorption severely limits the application of Mn^(2+)-activated narrowband green phosphors.Herein,a strategy to improve the absorption of Mn^(2+)-activated phosphors is proposed by selecting a suit able host to achieve a high doping concentration of Mn^(2+).Specifically,a magnetoplumbite-type com pound La_(0.827)Al_(11.9)O_(19.09)with a unique layered structure is selected as the host to accommodate Mn^(2+)(La_(0.827)Al_(11.9−x)Mn_(x)O_(19.09),LAO:xMn^(2+))and a high doping concentration of x=0.30 is obtained.Upon 450 nmexcitation,the prepared phosphor LAO:0.30Mn^(2+)displays an intense narrowband green emission peaking at 517 nm with a full width at half-maximum(FWHM)of 28 nm,a color purity of 88%and an internal/external quantum yield of 90%/16%.Furthermore,it exhibits a low thermal quenching(6%at 423 K)and negligible color drifting(3.29‰at 423 K).The LED device fabricated from the green phosphor LAO:0.30Mn^(2+),the commercial red phosphor K_(2)TiF_(6):Mn^(4+)and a blue InGaN chip can emit bright white light with a corresponding correlated color temperature(CCT)of 5464 K and a color gamut value of 124%of the National Television Commission(NTSC)standard.These results indicate that the LAO:0.30Mn^(2+)phosphor has great potential for usage as a green component in wide-color gamut LCD backlight applications.展开更多
基金supported by the Natural Science Foundation of China(No.11974351)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ114).
文摘Weak blue light absorption severely limits the application of Mn^(2+)-activated narrowband green phosphors.Herein,a strategy to improve the absorption of Mn^(2+)-activated phosphors is proposed by selecting a suit able host to achieve a high doping concentration of Mn^(2+).Specifically,a magnetoplumbite-type com pound La_(0.827)Al_(11.9)O_(19.09)with a unique layered structure is selected as the host to accommodate Mn^(2+)(La_(0.827)Al_(11.9−x)Mn_(x)O_(19.09),LAO:xMn^(2+))and a high doping concentration of x=0.30 is obtained.Upon 450 nmexcitation,the prepared phosphor LAO:0.30Mn^(2+)displays an intense narrowband green emission peaking at 517 nm with a full width at half-maximum(FWHM)of 28 nm,a color purity of 88%and an internal/external quantum yield of 90%/16%.Furthermore,it exhibits a low thermal quenching(6%at 423 K)and negligible color drifting(3.29‰at 423 K).The LED device fabricated from the green phosphor LAO:0.30Mn^(2+),the commercial red phosphor K_(2)TiF_(6):Mn^(4+)and a blue InGaN chip can emit bright white light with a corresponding correlated color temperature(CCT)of 5464 K and a color gamut value of 124%of the National Television Commission(NTSC)standard.These results indicate that the LAO:0.30Mn^(2+)phosphor has great potential for usage as a green component in wide-color gamut LCD backlight applications.
