Improvement in Luminous Efficacy and Thermal Performance Using Quantum Dots Spherical Shell for White Light Emitting Diodes

Songmao Chen; Caiman Yan; Yong Tang; Jiasheng Li; Xinrui Ding; Longshi Rao; Zongtao Li

doi:10.3390/nano8080618

Improvement in Luminous Efficacy and Thermal Performance Using Quantum Dots Spherical Shell for White Light Emitting Diodes

Nanomaterials (Basel). 2018 Aug 15;8(8):618. doi: 10.3390/nano8080618.

Authors

Songmao Chen¹, Caiman Yan², Yong Tang³, Jiasheng Li^{4

5}, Xinrui Ding⁶, Longshi Rao⁷, Zongtao Li^{8

9}

Affiliations

¹ Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. smchen@scut.edu.cn.
² Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. chamenyan@163.com.
³ Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. ytang@scut.edu.cn.
⁴ Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. jiasli@foxmail.com.
⁵ Foshan Nationstar Optoelectronics Company Ltd., Foshan 528000, China. jiasli@foxmail.com.
⁶ Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. ding.xinrui@mail.scut.edu.cn.
⁷ Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. memerls@mail.scut.edu.cn.
⁸ Key Laboratory of Surface Functional Structure Manufacturing of Guangdong High Education Institutes, South China University of Technology, Guangzhou 510641, China. meztli@scut.edu.cn.
⁹ Foshan Nationstar Optoelectronics Company Ltd., Foshan 528000, China. meztli@scut.edu.cn.

Abstract

White light-emitting diodes (WLEDs) based on quantum dots (QDs) are gaining increasing attention due to their excellent color quality. QDs films with planar structure are universally applied in WLEDs for color conversion, while they still face great challenges in high light extraction and thermal stability. In this study, a QDs film with a spherical shell structure was proposed to improve the optical and thermal performance for WLEDs. Compared with the conventional planar structure, the luminous efficacy of the QDs spherical shell structure is improved by 12.9% due to the reduced total reflection effect, and the angular-dependent correlated color temperature deviation is decreased from 2642 to 283 K. Moreover, the highest temperature of the WLED using a QDs spherical shell is 4.8 °C lower than that of the conventional WLED with a planar structure, which is mainly attributed to larger heat dissipation area and separated heat source. Consequently, this QDs spherical shell structure demonstrates superior performance of QDs films for WLEDs applications.

Keywords: chip-on-board; quantum dots; spherical shell structure; white light-emitting diode.