Pursuit of an ultrafast and highly efficient method to fabricate homogeneous carbon quantum dots (CQDs) with high quantum yield is a persistent objective for photoluminescence (PL) mechanism and bioimaging. Here, the CQDs were fabricated through ablation of low-cost carbon cloth by ultrafast and highly efficient dual-beam pulsed laser ablation. Unlike previous reports, a single laser beam is divided into double beams by a beam splitter in this work for shortening laser ablation time and improving ablation yield. More importantly, the obtained CQDs are more homogeneous than those obtained by single-beam pulsed laser ablation, and the corresponding quantum yield of emission is as high as 35.4%. The homogeneous CQDs show a stable and excitation-independent PL emission, which is attributed to the electron transition from the π∗ state to the surface state rather than from the π∗ state to the π state based on our experimental evidence. Furthermore, the CQDs have a good stability and excellent antijamming performance, which are well suitable for cell bioimaging. Therefore, a ‘dual-beam pulsed ablation’ technique proposed as an ultrafast method is used to fabricate homogeneous CQDs with high quantum yield for the study of PL emission mechanism and cell bioimaging.

追求超快速，高效的方法来制造具有高量子产率的均质碳量子点（CQD）是光致发光（PL）机理和生物成像的持久目标。在这里，CQD是通过超快速高效的双光束脉冲激光烧蚀对低成本碳布进行烧蚀而制成的。与以前的报告不同，在这项工作中，单个激光束被分束器分成双束，以缩短激光烧蚀时间并提高烧蚀产量。更重要的是，所获得的CQD比单束脉冲激光烧蚀所获得的CQD更均匀，相应的发射量子产率高达35.4％。均质CQD显示出稳定且与激发无关的PL发射，根据我们的实验证据，这归因于电子从π*态向表面态转变，而不是从π*态向π态转变。此外，CQD具有良好的稳定性和出色的抗干扰性能，非常适合用于细胞生物成像。因此，作为超快方法提出的“双束脉冲烧蚀”技术被用于制造具有高量子产率的均质CQD，用于研究PL发射机理和细胞生物成像。