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A high-performance white-light-emitting-diodes based on nano-single crystal divanadates quantum dots.

ABSTRACT: We report a high-performance phosphors-free white light-emitting-diodes (w-LEDs) using Ba2V2O7 or Sr2V2O7 quantum dots that directly heteroepitaxially grown on common quartz substrates by polymer assisted deposition (PAD). The quantum efficiency of quantum dots is as high as 95%. More importantly, electronic local functions, band structure and partial density of states have been firstly calculated to study the luminescent and heteroepitaxial growth mechanisms by the Ab-initio Simulation. Additionally, the glaring white light excited at a wavelength of 325?nm was experimentally observed, which unambiguously demonstrated that such quantum dots can be efficient w-LEDs for solid state lighting.

SUBMITTER: Yang W

PROVIDER: S-EPMC4437379 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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A high-performance white-light-emitting-diodes based on nano-single crystal divanadates quantum dots.

Yang Weiqing W Liu Zhongli Z Chen Jun J Huang Li L Zhang Lei L Pan Hong H Wu Bo B Lin Yuan Y

Scientific reports 20150519

We report a high-performance phosphors-free white light-emitting-diodes (w-LEDs) using Ba2V2O7 or Sr2V2O7 quantum dots that directly heteroepitaxially grown on common quartz substrates by polymer assisted deposition (PAD). The quantum efficiency of quantum dots is as high as 95%. More importantly, electronic local functions, band structure and partial density of states have been firstly calculated to study the luminescent and heteroepitaxial growth mechanisms by the Ab-initio Simulation. Additio ...[more]

PMID: 25989049

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