采用逐步热注射法合成了用于白光LED的CuInS2/ZnS(CIS/ZnS)核壳结构量子点。通过调整Cu/In的比率,在CuInS2(CIS)量子点的基础上,合成了发射波长在570~650 nm之间可调的CIS/ZnS量子点。与CIS量子点的低量子产率相比,具有核壳结构的CIS/ZnS量子点的量子产率达到了78%。通过在黄光荧光粉YAG∶Ce3+表面旋涂CIS/ZnS量子点的方式制备了暖白光LED器件。在工作电流为10 mA时,暖白光LED的发光效率达到了244.58 lm/W。由于CIS/ZnS量子点的加入,所制备的白光LED器件的显色指数达到86.7且发光颜色向暖色调发生了转移,相应的色坐标为(0.340 6,0.369 0)。

A stepwise hot-injection method was proposed to synthesize CuInS2/ZnS (CIS/ZnS) core/shell quantum dots. Based on CIS quantum dots,the emission bands of the prepared CIS/ZnS quantum dots can be tuned from 570 to 650 nm by varying Cu/In ratio. Compared to the low quantum yields of CIS quantum dots,the quantum yields of CIS/ZnS core/shell quantum dots can reach 78%. The white LEDs with warm tone were successfully obtained via spin-coating CIS/ZnS quantum dots on the yellow phosphor YAG∶Ce3+. The experimental results indicate that the white LEDs possess high luminous efficiency of 244.58 lm/W under 10 mA current density. As a result of joining CIS/ZnS quantum dots,the prepared white LEDs display higher color rendering index (CRI) of about 82.7 and warm white light with a correlated CIE parameters of (0.340 6,0.369 0).