近日，西南科大制造过程测试技术教育部重点实验室微纳仿生制造团队报道了一种针对多相有机液体分离与运输策略，研究成果以题目为“Ultrafast self-transportation and efficient separation of organic droplets on semi-conical asymmetric structure”发表于物理学科领域国际期刊Applied Physics Letters（Appl. Phys. Lett. 124, 161902, 2024 ）。 该期刊由美国物理学会（AIP）出版的国际权威物理学期刊，为82种自然指数期刊之一，该期刊涵盖了广泛的物理学领域，包括材料科学、光学、电子学、凝聚态物理、应用物理等。 我校青年教师杨益博士和硕士研究生邹秦锐为该成果的共同第一作者，李国强教授为通讯作者。
In the context of industrial production and environmental protection, the manipulation and separation of organic multiphase droplets has always been a significant and challenging task. Organic droplets play an important role in industrial production as lubricants, fuels or chemical feedstocks. Traditional separation methods such as extraction, distillation, chromatography, recrystallization, and membrane separation have been used for the separation of organic mixed liquids, but the disadvantages of these methods such as high energy consumption, chemical failure, and structural clogging limit their wide application. In addition, these traditional methods are often accompanied by large amounts of carbon dioxide emissions, which is contrary to the concept of "carbon neutral" green development advocated by the mainland. Therefore, the development of an efficient, low-consumption and environmentally friendly green separation technology for organic mixed liquids has become an important challenge in the fields of energy development, environmental protection and public health.
In order to solve the urgent problem of efficient and accurate separation of organic mixed liquids, the research team designed and constructed a novel semi-conical asymmetric structure (SCAS). This structure combines a tapered structure with an anisotropic micro-groove structure to demonstrate excellent directional self-transport performance for organic liquids. The results show that the maximum transmission speed of SCAS reaches 305.6 mm/s, which shows excellent transportation performance compared with the traditional conical structure, fluted fishbone structure and cylindrical structure, and the transportation speed is 1.8 times that of the traditional conical structure. By constructing a physical model between the surface structure parameters and the droplet transport velocity, the law of "differential" transport and directional transport of each component in the mixture under the action of the coupling droplet surface energy difference and the unidirectional driving force of the fluid diode is clarified, and the high-performance control of the droplet in the multi-component mixture with the efficient and accurate separation of each component as an example is realized, and the separation efficiency reaches 98%. At the same time, SCAS has good stability and continuous transport performance, and the transport rate does not decrease significantly in 5 cycles (7 days per cycle), which enables it to maintain efficient and continuous droplet transport in practical applications. This discovery provides support for the wide application of high-performance droplet manipulation, which is typified by efficient and precise oil-water separation.
The micro-nano bionic manufacturing team has been committed to combining the cutting-edge bionic design concept of "from nature, higher than nature" with advanced micro-nano precision manufacturing technology, and building strategies for high-performance droplet control devices in the fields of energy, environment and health. In recent years, the team has reported a series of research results on micro-nano fabrication and applications, including janus membranes (Nat. Commun., 2024, 15, 1443); Commun., 2023, 14, 1928); Mater., 2020, 32, 2005039); Funct. Mater., 2022, 32, 2201035), femtosecond laser-induced ultrafast self-growth of mushroom head-shaped micropillars (Nano Lett., 2021, 21, 9301-9309), high-performance droplet manipulation (Nano-Micro Lett., 2022, 14, 97), and high-performance liquid metal electromagnetic driver (IJEM, 2021, 6, 025503).
Source: Frontiers of Polymer Science