Near-infrared emission of Yb3＋ and Bi3＋-co-doped GdVO4 vanadate phosphors obtained via the modified Pechini＇s method was reported. The phase purity and structure of samples were characterized by X-ray powder diN＇a...Near-infrared emission of Yb3＋ and Bi3＋-co-doped GdVO4 vanadate phosphors obtained via the modified Pechini＇s method was reported. The phase purity and structure of samples were characterized by X-ray powder diN＇action （XRD）, X-ray energy disper- sion spectroscopy （EDS）, scanning electron microscopy （SEM）, Raman and infrared （IR） spectroscopy. Photoluminescence emission （PL） and excitation （PLE） spectra were recorded and investigated in details. Results indicated that upon near-UV excitation （340 nm） in the （Bi3＋-V5＋） charge transfer state this phosphor had a strong broad band yellow-green emission （3Pi--ISo） of Bi3＋ ions and also NIR emission （2Fs/2-2Fv/2） of Yb3＋ ions in the range of 950-1050 nm, which matched well with the spectral response of the sili- con-based solar cells. The decreasing Bi3＋ emission with increasing Yb3＋ concentration proved the occurrence of energy transfer from Bi3＋ to Yb3＋ ions. Results demonstrated that Yb3＋ and Bi3＋-co-doped GdVO4 vanadate phosphors might act as a NIR down-conversion （DC） solar spectral converter to enhance the efficiency of the silicon-based solar cells.展开更多
In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce^(3+)/Er^(3+) doped La_3Si_6N_(11) was designed and firstly prepared via conventional solid...In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce^(3+)/Er^(3+) doped La_3Si_6N_(11) was designed and firstly prepared via conventional solid-state reactions. The structure and morphology of Ce^(3+)/Er^(3+) doped La_3Si_6N_(11) were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Compared with Er^(3+) doped La_3Si_6N_(11),the emission intensity of the Ce^(3+), Er^(3+) co-doped phosphor can be increased more than 5 times.Meanwhile, the mechanism of energy transfer from Ce^(3+) to Er^(3+) is confirmed according to the excitation,emission spectra and decay lifetimes curve. Above results suggest that La_3 Si_6 N_(11):Ce^(3+),Er^(3+) is a promising near-infrared phosphor for blue pumped LEDs(light-emitting diodes).展开更多
近红外光谱技术在安防监控、食品检测、生物成像、农业等领域具有重要应用价值,而开发出紧凑高效的近红外光源是其大规模商业应用的前提.荧光粉转换型近红外发光二极管(light emitting diodes,LED)光源具有结构紧凑、成本低、使用寿命...近红外光谱技术在安防监控、食品检测、生物成像、农业等领域具有重要应用价值,而开发出紧凑高效的近红外光源是其大规模商业应用的前提.荧光粉转换型近红外发光二极管(light emitting diodes,LED)光源具有结构紧凑、成本低、使用寿命长、发射光谱可调等优点,因此近些年受到广泛关注,其关键就在于开发出能被蓝光有效激发的高性能近红外荧光粉.本工作利用高温固相法制备了一种新型宽带近红外荧光粉 In_(2)BP_(3)O_(12):Cr^(3+),在 480 nm 激发下,荧光粉发射峰值位于 950 nm,光谱覆盖了 750~1350 nm 范围,半峰宽达到 210 nm.采用该荧光粉与商用蓝光 In Ga N LED 芯片封装,获得了具有宽带发射的近红外 LED 光源,在 60 mA 的驱动电流下,近红外光辐射功率为 5 mW.当采用该光源照射人的手掌,用近红外电感耦合器(charge coupled device,CCD)相机能够对手掌中的血管进行清晰的成像.上述结果表明该近红外荧光粉可用于制备基于蓝光芯片的宽带近红外 LED 光源,并在生物医学等领域具有潜在应用前景.展开更多
文摘Near-infrared emission of Yb3＋ and Bi3＋-co-doped GdVO4 vanadate phosphors obtained via the modified Pechini＇s method was reported. The phase purity and structure of samples were characterized by X-ray powder diN＇action （XRD）, X-ray energy disper- sion spectroscopy （EDS）, scanning electron microscopy （SEM）, Raman and infrared （IR） spectroscopy. Photoluminescence emission （PL） and excitation （PLE） spectra were recorded and investigated in details. Results indicated that upon near-UV excitation （340 nm） in the （Bi3＋-V5＋） charge transfer state this phosphor had a strong broad band yellow-green emission （3Pi--ISo） of Bi3＋ ions and also NIR emission （2Fs/2-2Fv/2） of Yb3＋ ions in the range of 950-1050 nm, which matched well with the spectral response of the sili- con-based solar cells. The decreasing Bi3＋ emission with increasing Yb3＋ concentration proved the occurrence of energy transfer from Bi3＋ to Yb3＋ ions. Results demonstrated that Yb3＋ and Bi3＋-co-doped GdVO4 vanadate phosphors might act as a NIR down-conversion （DC） solar spectral converter to enhance the efficiency of the silicon-based solar cells.
基金Project supported by Key Strategic Advanced Electronic Materials Department of the Ministry of Science and Technology,(2017YFB0404300,2017YFB0404301)
文摘In order to obtain near-infrared phosphor pumped by blue chip with high luminous efficiency, a novel near-infrared phosphor Ce^(3+)/Er^(3+) doped La_3Si_6N_(11) was designed and firstly prepared via conventional solid-state reactions. The structure and morphology of Ce^(3+)/Er^(3+) doped La_3Si_6N_(11) were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Compared with Er^(3+) doped La_3Si_6N_(11),the emission intensity of the Ce^(3+), Er^(3+) co-doped phosphor can be increased more than 5 times.Meanwhile, the mechanism of energy transfer from Ce^(3+) to Er^(3+) is confirmed according to the excitation,emission spectra and decay lifetimes curve. Above results suggest that La_3 Si_6 N_(11):Ce^(3+),Er^(3+) is a promising near-infrared phosphor for blue pumped LEDs(light-emitting diodes).
文摘近红外光谱技术在安防监控、食品检测、生物成像、农业等领域具有重要应用价值,而开发出紧凑高效的近红外光源是其大规模商业应用的前提.荧光粉转换型近红外发光二极管(light emitting diodes,LED)光源具有结构紧凑、成本低、使用寿命长、发射光谱可调等优点,因此近些年受到广泛关注,其关键就在于开发出能被蓝光有效激发的高性能近红外荧光粉.本工作利用高温固相法制备了一种新型宽带近红外荧光粉 In_(2)BP_(3)O_(12):Cr^(3+),在 480 nm 激发下,荧光粉发射峰值位于 950 nm,光谱覆盖了 750~1350 nm 范围,半峰宽达到 210 nm.采用该荧光粉与商用蓝光 In Ga N LED 芯片封装,获得了具有宽带发射的近红外 LED 光源,在 60 mA 的驱动电流下,近红外光辐射功率为 5 mW.当采用该光源照射人的手掌,用近红外电感耦合器(charge coupled device,CCD)相机能够对手掌中的血管进行清晰的成像.上述结果表明该近红外荧光粉可用于制备基于蓝光芯片的宽带近红外 LED 光源,并在生物医学等领域具有潜在应用前景.
