[20p-235-1~15] 13.8 Optical properties and light-emitting devices

[20p-235-7] Band-edge emission from AgInS₂/GaS_x core/shell colloidal quantum dots and improvement of optical properties

〇Taro Uematsu¹, Kazutaka Wajima¹, Dharmendar Kumar Sharma², Shuzo Hirata², Takahisa Yamamoto³, Tatsuya Kameyama³, Martin Vacha², Tsukasa Torimoto³, Daisuke Oyamatsu⁴, Susumu Kuwabata¹ (1.Osaka Univ., 2.Tokyo Tech., 3.Nagoya Univ., 4.Nichia Corporation)

Keywords:colloidal quantum dots, band-edge emission, cadmium-free

Cadmium-free quantum dots have been a center of research activities in the world as alternative to CdSe photoluminescent quantum dots possessing prominent optical properties. We have succeeded in generating a narrow band-edge emission from AgInS₂ quantum dots by coating them with an amorphous gallium sulfide (GaS_x) shells. The present paper describes a remarkable improvement of quantum yield (56%) and spectral monochromaticity (single peak, FWHM = 140 meV) by several modifications to the AgInS₂ cores, GaS_x shells, and chemical passivation of the shell surface.