采用溶胶-凝胶法制备出Y_(2-2 x)MgTiO_(6)∶2 x Eu^(3+)(YMT∶2 x Eu^(3+),0≤x≤0.11)新型红色荧光粉。通过X射线衍射仪(XRD)检测样品的纯度,结果显示YMT∶Eu^(3+)样品属于单斜晶系,空间群为P21/n,无其他杂相。扫描电子显微镜(SEM)照...采用溶胶-凝胶法制备出Y_(2-2 x)MgTiO_(6)∶2 x Eu^(3+)(YMT∶2 x Eu^(3+),0≤x≤0.11)新型红色荧光粉。通过X射线衍射仪(XRD)检测样品的纯度,结果显示YMT∶Eu^(3+)样品属于单斜晶系,空间群为P21/n,无其他杂相。扫描电子显微镜(SEM)照片显示荧光粉为2μm的不规则颗粒。当激发波长为264 nm时,发射光谱出现四个尖锐的发射峰,分别位于591(^(5)D_(0)→^(7)F_(1))、619(^(5)D_(0)→^(7)F_(2))、657(^(5)D_(0)→^(7)F_(3))和693 nm(^(5)D_(0)→^(7)F_(4))。Eu^(3+)离子之间能量传递为电偶极子-电偶极子(d-d)相互作用。YMT∶0.14Eu^(3+)荧光粉的CIE色度坐标为(0.645,0.332),与红光标准色坐标(0.67,0.33)非常接近。变温PL光谱及热激活能计算结果显示荧光粉具有一定的热稳定性,因此YMT∶Eu^(3+)是一种具有潜在应用价值的LED红色荧光粉。展开更多
A series of novel luminescent materials, SrZnO2:M (M=Eu3+, or Eu3+ + Li+) have been synthesized by high-temperature solid-state reaction. The structure and luminescence properties of SrZnO2:Eu3+ phosphor were studied ...A series of novel luminescent materials, SrZnO2:M (M=Eu3+, or Eu3+ + Li+) have been synthesized by high-temperature solid-state reaction. The structure and luminescence properties of SrZnO2:Eu3+ phosphor were studied through XRD, photoluminescence and Raman spectroscopy. The excitation spectra show a broad intense band and a number of small peaks corresponding to the inner 4f-shell excitations of Eu3+ (the strongest one is at 395 nm for 7F0-5L6). After SrZnO2:Eu3+ phosphor was co-doped with Li+ ions, its charge transfer band extended to longer wavelengths. This resulted in increase of luminescent quantum efficiency of the sample. SrZnO2:Eu3+,Li+ phosphor can be efficiently excited by longer UV. From the fluorescence spectrum of SrZnO2:Eu3+ phosphor, apart from transition emissions of 5D0 → 7FJ (J=0~4), the transition emissions from 5D1 → 7FJ (J=0~2) have been observed. For the SrZnO2:Eu3+ phosphor, under excitation of UV, the dominant emission is at about 612 nm, due to the 5D0 → 7F2 hypersensitive transition. The incorporation of Li+ ions greatly enhanced the luminescence intensity and made emission peak from 5D0 → 7F2 transition red-shifted.展开更多
SrZnO2 ： Eu^3 ＋ , Li^＋ phosphor powder by long wavelength UV excitation was synthesized by conventional solid-state reaction method. XRD and PL were employed to characterize their properties. The resuits show that ...SrZnO2 ： Eu^3 ＋ , Li^＋ phosphor powder by long wavelength UV excitation was synthesized by conventional solid-state reaction method. XRD and PL were employed to characterize their properties. The resuits show that Eu^3＋ ions preferentially occupy Sr^2＋ asymmetry cationic sites, thus emitting 612 nm red light originated from ^5D0 to ^7F2 transition. The luminescent intensity can be greatly enhanced with incorporation of Li^＋ ions. The excitation efficiency in range of 350 - 400 nm also increases greatly due to incorporating Li ^＋ ions. SrZnO2 ： Eu^3 ＋ , Li^＋ is a promising redemitting phosphor by long wavelength UV excitation.展开更多
文摘采用溶胶-凝胶法制备出Y_(2-2 x)MgTiO_(6)∶2 x Eu^(3+)(YMT∶2 x Eu^(3+),0≤x≤0.11)新型红色荧光粉。通过X射线衍射仪(XRD)检测样品的纯度,结果显示YMT∶Eu^(3+)样品属于单斜晶系,空间群为P21/n,无其他杂相。扫描电子显微镜(SEM)照片显示荧光粉为2μm的不规则颗粒。当激发波长为264 nm时,发射光谱出现四个尖锐的发射峰,分别位于591(^(5)D_(0)→^(7)F_(1))、619(^(5)D_(0)→^(7)F_(2))、657(^(5)D_(0)→^(7)F_(3))和693 nm(^(5)D_(0)→^(7)F_(4))。Eu^(3+)离子之间能量传递为电偶极子-电偶极子(d-d)相互作用。YMT∶0.14Eu^(3+)荧光粉的CIE色度坐标为(0.645,0.332),与红光标准色坐标(0.67,0.33)非常接近。变温PL光谱及热激活能计算结果显示荧光粉具有一定的热稳定性,因此YMT∶Eu^(3+)是一种具有潜在应用价值的LED红色荧光粉。
文摘A series of novel luminescent materials, SrZnO2:M (M=Eu3+, or Eu3+ + Li+) have been synthesized by high-temperature solid-state reaction. The structure and luminescence properties of SrZnO2:Eu3+ phosphor were studied through XRD, photoluminescence and Raman spectroscopy. The excitation spectra show a broad intense band and a number of small peaks corresponding to the inner 4f-shell excitations of Eu3+ (the strongest one is at 395 nm for 7F0-5L6). After SrZnO2:Eu3+ phosphor was co-doped with Li+ ions, its charge transfer band extended to longer wavelengths. This resulted in increase of luminescent quantum efficiency of the sample. SrZnO2:Eu3+,Li+ phosphor can be efficiently excited by longer UV. From the fluorescence spectrum of SrZnO2:Eu3+ phosphor, apart from transition emissions of 5D0 → 7FJ (J=0~4), the transition emissions from 5D1 → 7FJ (J=0~2) have been observed. For the SrZnO2:Eu3+ phosphor, under excitation of UV, the dominant emission is at about 612 nm, due to the 5D0 → 7F2 hypersensitive transition. The incorporation of Li+ ions greatly enhanced the luminescence intensity and made emission peak from 5D0 → 7F2 transition red-shifted.
文摘SrZnO2 ： Eu^3 ＋ , Li^＋ phosphor powder by long wavelength UV excitation was synthesized by conventional solid-state reaction method. XRD and PL were employed to characterize their properties. The resuits show that Eu^3＋ ions preferentially occupy Sr^2＋ asymmetry cationic sites, thus emitting 612 nm red light originated from ^5D0 to ^7F2 transition. The luminescent intensity can be greatly enhanced with incorporation of Li^＋ ions. The excitation efficiency in range of 350 - 400 nm also increases greatly due to incorporating Li ^＋ ions. SrZnO2 ： Eu^3 ＋ , Li^＋ is a promising redemitting phosphor by long wavelength UV excitation.
