Phosphor-converted white light-emitting diodes for indoor illumination need to be warm-white(i.e.,correlated color temperature,4000 K)with good color rendition(i.e.,color rendering index.80).However,no single-phosphor...Phosphor-converted white light-emitting diodes for indoor illumination need to be warm-white(i.e.,correlated color temperature,4000 K)with good color rendition(i.e.,color rendering index.80).However,no single-phosphor,single-emitting-center-converted white light-emitting diodes can simultaneously satisfy the color temperature and rendition requirements due to the lack of sufficient red spectral component in the phosphors’emission spectrum.Here,we report a new yellow Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor that has a new orthorhombic lattice structure and exhibits a broad yellow photoluminescence band with sufficient red spectral component.Warm-white emissions with correlated color temperature,4000 K and color rendering index.80 were readily achieved when combining the Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor with a blue light-emitting diode(440–470 nm).This study demonstrates that warm-white light-emitting diodes with high color rendition(i.e.,color rendering index.80)can be achieved based on single-phosphor,single-emitting-center conversion.展开更多
基金ZWP acknowledges funding by the US National Science Foundation(CAREER DMR-0955908)ZJG acknowledges support by the National Basic Research Programs of China(973 program,No.2012CB932504)+4 种基金JDB was supported by the Materials Sciences and Engineering Division,Office of Basic Energy Sciences(BES),US Department of Energy(DOE).Use of the APS beamline 11-BM-B for synchrotron X-ray powder diffractionbeamline 34-ID-E for polychromatic Laue microdiffraction was supported by the Scientific User Facilities Division of BES,US DOE.Use of the APS beamline 20-BM-B for X-ray absorption near edge structure measurement by CJS was supported by US DOE under Contract no.DE-AC02-06CH11357 with Argonne National Laboratory.The TEM characterization was sponsored by Oak Ridge National Laboratory’s Shared Research Equipment(ShaRE)User program,which is sponsored by the Division of Scientific User Facilities of BES,US DOE.
文摘Phosphor-converted white light-emitting diodes for indoor illumination need to be warm-white(i.e.,correlated color temperature,4000 K)with good color rendition(i.e.,color rendering index.80).However,no single-phosphor,single-emitting-center-converted white light-emitting diodes can simultaneously satisfy the color temperature and rendition requirements due to the lack of sufficient red spectral component in the phosphors’emission spectrum.Here,we report a new yellow Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor that has a new orthorhombic lattice structure and exhibits a broad yellow photoluminescence band with sufficient red spectral component.Warm-white emissions with correlated color temperature,4000 K and color rendering index.80 were readily achieved when combining the Ba_(0.93)Eu_(0.07)Al_(2)O_(4) phosphor with a blue light-emitting diode(440–470 nm).This study demonstrates that warm-white light-emitting diodes with high color rendition(i.e.,color rendering index.80)can be achieved based on single-phosphor,single-emitting-center conversion.
