Eu3＋-doped ZnMoO4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu3＋ doping on the phase structure and photoluminescence （PL） properties of ZnMoO4 were investigated...Eu3＋-doped ZnMoO4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu3＋ doping on the phase structure and photoluminescence （PL） properties of ZnMoO4 were investigated. The result showed that the introduction of Eu3~ could lead to phase transition of ZnMoO4. With the increase of Eu3-- doping amount, [3-ZnMoO4 was transformed to ct phase gradually, which led to different photoluminescence performances. The optimized doping concentration of Eu3＋ was 6 mol% for the highest emission intensity at 615 nm. Its CIE chromaticity coordinates were （0.667, 0.331）, which were very close to the values of standard chromaticity （0.67, 0.33） for National Television Standards Committee （NTSC） system. Therefore, Eu3＋-doped ZnMoO4 is considered to be a promising red-emitting phosphor for white LED applications.展开更多
Achieving high-efficiency deep blue emitter with CIE_(y)<0.06(CIE,Commission Internationale de L’Eclairage)and external quantum efficiency(EQE)>10%has been a long-standing challenge for traditional fluorescent ...Achieving high-efficiency deep blue emitter with CIE_(y)<0.06(CIE,Commission Internationale de L’Eclairage)and external quantum efficiency(EQE)>10%has been a long-standing challenge for traditional fluorescent materials in organic light-emitting diodes(OLEDs).Here,we report the rational design and synthesis of two new deep blue luminogens:4-(10-(4’-(9 H-carbazol-9-yl)-2,5-dimethyl-[1,1’-biphe nyl]-4-yl)anthracen-9-yl)benzonitrile(2 M-ph-pCzAnBzt)and 4-(10-(4-(9 H-carbazol-9-yl)-2,5-dimethyl phenyl)anthracen-9-yl)benzonitrile(2 M-pCzAnBzt).In particular,2 M-ph-pCzAnBzt produces saturated deep blue emissions in a non-doped electroluminescent device with an exceptionally high EQE of 10.44% and CIE_(x,y)(0.151,0.057).The unprecedented electroluminescent efficiency is attributed to the combined effects of higher-order reversed intersystem crossing and triplet-triplet up-conversion,which are supported by analysis of theoretical calculation,triplet sensitization experiments,as well as nanosecond transient absorption spectroscopy.This research offers a new approach to resolve the shortage of high efficiency deep blue fluorescent emitters.展开更多
文摘Eu3＋-doped ZnMoO4 with different doping concentrations were synthesized by a hydrothermal method. The effects of Eu3＋ doping on the phase structure and photoluminescence （PL） properties of ZnMoO4 were investigated. The result showed that the introduction of Eu3~ could lead to phase transition of ZnMoO4. With the increase of Eu3-- doping amount, [3-ZnMoO4 was transformed to ct phase gradually, which led to different photoluminescence performances. The optimized doping concentration of Eu3＋ was 6 mol% for the highest emission intensity at 615 nm. Its CIE chromaticity coordinates were （0.667, 0.331）, which were very close to the values of standard chromaticity （0.67, 0.33） for National Television Standards Committee （NTSC） system. Therefore, Eu3＋-doped ZnMoO4 is considered to be a promising red-emitting phosphor for white LED applications.
基金supported by the National Natural Science Foundation of China(62004074,51727809)the Science and Technology Department of Hubei Province(2019AAA063,2020BAA016)。
文摘Achieving high-efficiency deep blue emitter with CIE_(y)<0.06(CIE,Commission Internationale de L’Eclairage)and external quantum efficiency(EQE)>10%has been a long-standing challenge for traditional fluorescent materials in organic light-emitting diodes(OLEDs).Here,we report the rational design and synthesis of two new deep blue luminogens:4-(10-(4’-(9 H-carbazol-9-yl)-2,5-dimethyl-[1,1’-biphe nyl]-4-yl)anthracen-9-yl)benzonitrile(2 M-ph-pCzAnBzt)and 4-(10-(4-(9 H-carbazol-9-yl)-2,5-dimethyl phenyl)anthracen-9-yl)benzonitrile(2 M-pCzAnBzt).In particular,2 M-ph-pCzAnBzt produces saturated deep blue emissions in a non-doped electroluminescent device with an exceptionally high EQE of 10.44% and CIE_(x,y)(0.151,0.057).The unprecedented electroluminescent efficiency is attributed to the combined effects of higher-order reversed intersystem crossing and triplet-triplet up-conversion,which are supported by analysis of theoretical calculation,triplet sensitization experiments,as well as nanosecond transient absorption spectroscopy.This research offers a new approach to resolve the shortage of high efficiency deep blue fluorescent emitters.
