Yu Anhui, Guo Zhiguang
Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Key Laboratory of Polymer Materials, Hubei University, Wuhan, 430062, China.
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, China.
Small. 2025 Jun;21(25):e2412695. doi: 10.1002/smll.202412695. Epub 2025 May 2.
The directional transport and precise control of droplets and bubbles are crucial for future applications, but remain challenging due to complex fluid dynamics and application limits. In light of existing research on droplet manipulation, a MnO/carbon microsphere (MnO/Cs) covalently grafted lubricant-infused slippery surface (SPM) is designed for the manipulation of droplets and bubbles. The structure and morphology of the MnO/Cs are examined using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM), and the elemental composition and chemical bonds of the compounds are characterized by X-ray photoelectron spectroscopy (XPS), Raman spectra and Fourier transform infrared spectrometer (FTIR). The SPM with a sliding angle as low as 3° is prepared. On the SPM, the rapid transportation and precise control of small droplets can be achieved, with the transportation speed of 5 µL droplets reaching 1 mm s and the round-trip control of droplets also being feasible. The surface is capable of controlling the speed of a 100 µL droplet with a precision of 0.49 mm s, while a 50 µL droplet can be directed with a load of 1 mg. Moreover, bubbles with a volume of 5 to 20 µL can also be transported.
液滴和气泡的定向传输与精确控制对于未来的应用至关重要，但由于复杂的流体动力学和应用限制，仍然具有挑战性。鉴于现有的液滴操纵研究，设计了一种共价接枝有润滑剂的MnO/碳微球（MnO/Cs）光滑表面（SPM）来操纵液滴和气泡。使用X射线衍射（XRD）和场发射扫描电子显微镜（FESEM）对MnO/Cs的结构和形态进行了研究，并用X射线光电子能谱（XPS）、拉曼光谱和傅里叶变换红外光谱仪（FTIR）对化合物的元素组成和化学键进行了表征。制备了滑动角低至3°的SPM。在该SPM上，可以实现小液滴的快速传输和精确控制，5 μL液滴的传输速度达到1 mm/s，液滴的往返控制也可行。该表面能够以0.49 mm/s的精度控制100 μL液滴的速度，同时50 μL液滴在1 mg负载下可以被引导。此外，体积为5至20 μL的气泡也可以被传输。
