Improving the Performance of Near-infrared CuInSe2 Quantum Dots by Two Strategies: Doping and Ligand Exchange
Improving the Performance of Near-infrared CuInSe2 Quantum Dots by Two Strategies: Doping and Ligand Exchange
复制标题
通过掺杂和配体交换两种策略提高近红外 CuInSe2 量子点的性能
DOI：
10.1142/s1793292021500120
复制
发表时间：
2020
期刊：
影响因子：
1.2
通讯作者：
Pengtao Sheng
中科院分区：
文献类型：
--
作者：
Weili Li;Hongchao Geng;Lu Yao;Haiyan Xu;Yongjun Han;Pengtao Sheng
采用热注入法合成了油相CuInSe2量子点（CISe QDs），其近红外（NIR）发射波长为710 nm，荧光强度较差。因此，我们通过引入掺杂和配体交换两种策略来解决这一挑战。首先，用Zn作为掺杂剂，改善了用相同方法合成的CISe量子点的荧光性能。所得的Zn-CuInSe （ZnCISe）量子点的发光峰位置可以从600 nm调谐到662 nm，量子点的发光强度大大提高。此外，这种锌掺杂策略有助于提高荧光寿命，减少缺陷，从而提高量子产率。接下来，利用谷胱甘肽（GSH）作为双功能配体，通过有效的配体交换策略实现了ZnCISe量子点的水相转移。巯基乙酸（MPA）也被用作谷胱甘肽配体交换的必要添加剂。通过这种方法，我们获得了高质量的亲水性ZnCISe量子点，其粒径小于3 nm，单分散性好。此外，DLS测量显示，超纯水中水合ZnCISe量子点的峰形为单峰，粒径范围为7 nm ~ 40 nm。最后，细胞毒性研究表明，在1[公式：见文][公式：见文]g/mL ~ 18[公式：见文][公式：见文]g/mL范围内，ZnCISe量子点孵育的细胞活力保持在90%以上，表明具有良好生物相容性的量子点是很有前途的荧光探针。
Oil phase CuInSe2 quantum dots (CISe QDs) were synthesized via a hot-injection method, exhibiting a near-infrared (NIR) emission wavelength of 710[Formula: see text]nm with poor fluorescence intensity. Therefore, we address this challenge by introducing two strategies: doping and ligand exchange. First, Zn was used as a dopant to improve the fluorescent properties of CISe QDs synthesized by the same method. The PL peak position of the resulting Zn–CuInSe (ZnCISe) QDs could be tuned from 600[Formula: see text]nm to 662[Formula: see text]nm, and the PL intensity of the QDs was greatly improved. Except that, this Zn doping strategy can help to improve the fluorescence lifetime and reduce defects, leading to increased quantum yield. Next, the aqueous phase transfer of ZnCISe QDs was achieved through an efficient ligand exchange strategy using glutathione (GSH) as the bifunctional ligand. Mercaptoacetic acid (MPA) was also used as an essential additive for GSH ligand exchange. With this method, we obtained high-quality hydrophilic ZnCISe QDs with particle sizes less than 3[Formula: see text]nm and good monodispersity. In addition, DLS measurements showed a unimodal peak shape of the hydrated ZnCISe QDs in ultrapure water with particle sizes ranging from 7[Formula: see text]nm to 40[Formula: see text]nm. Finally, the cytotoxicity studies revealed that the viabilities of the cells incubated with ZnCISe QDs from 1[Formula: see text][Formula: see text]g/mL to 18[Formula: see text][Formula: see text]g/mL remained at levels greater than 90%, which indicates that QDs with good biocompatibility are promising fluorescent probes.