State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Biogas Upgrading Utilization, College of New Energy and Materials Science, China University of Petroleum-Beijing, Beijing, 102249, China.
Nanoscale. 2019 Aug 1;11(30):14123-14133. doi: 10.1039/c9nr04421c.
Quantum dots, derived from two-dimensional (2D) materials, have shown promise in bioimaging, sensing and photothermal applications, and in white light emitting devices (WLEDs). Herein, nitrogen and phosphorus functionalized Ti3C2 MXene based quantum dots (N,P-MQDs) were successfully prepared through a top-bottom hydrothermal method. This type of photoluminescent quantum dots has realized green fluorescence for the first time at around 560 nm with a photoluminescence quantum yield (PLQY) of 20.1%, the highest ever reported; meanwhile, it also exhibits excellent photostability and pH resistance capacities. Comprehensive characterization and well-resolved density functional theory (DFT) calculation were implemented to determine the mechanism of fluorescence shift and enhancement. Furthermore, the N,P-MQDs have been proved to efficiently act as fluorescent probes for macrophage labeling. In addition, the high sensitivity of the N,P-MQDs toward Cu2+ ions made them a low cost, sensitive, environment-friendly, and label-free fluorescence platform for Cu2+ detection. The outstanding performance of Ti3C2 MXene based quantum dots has demonstrated their great potential to be used as promising fluorescent probes in the fields of biological imaging, optical sensing, photoelectric conversion, etc.
量子点来源于二维（2D）材料，在生物成像、传感和光热应用以及白光发光器件（WLED）中显示出了应用前景。在此，通过自上而下的水热法成功制备了氮磷功能化 Ti3C2 MXene 基量子点（N，P-MQDs）。这种光致发光量子点首次在约 560nm 处实现了绿色荧光，光致发光量子产率（PLQY）为 20.1%，是迄今为止报道的最高值；同时，它还表现出优异的光稳定性和 pH 耐受力。进行了全面的表征和解析密度泛函理论（DFT）计算，以确定荧光位移和增强的机制。此外，N，P-MQDs 已被证明可有效地用作巨噬细胞标记的荧光探针。此外，N，P-MQDs 对 Cu2+离子的高灵敏度使其成为一种低成本、灵敏、环保且无标记的荧光平台，可用于 Cu2+检测。Ti3C2 MXene 基量子点的卓越性能表明，它们在生物成像、光学传感、光电转换等领域作为有前途的荧光探针具有巨大的潜力。
