TY - JOUR
T1 - Active steering of omni-droplets on slippery cross-scale arrays by bi-directional vibration
AU - Wu, Sizhu
AU - Xiang, Le
AU - Zhang, Yiyuan
AU - Jiang, Shaojun
AU - Li, Chuanzong
AU - Zhao, Zhipeng
AU - Zhang, Yiyuan
AU - Deng, Qiyu
AU - Xie, Shuting
AU - Jiao, Yunlong
AU - Chen, Chao
AU - Lao, Zhaoxin
AU - Wang, Liqiu
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (Grant Nos. 51875160 and 52175396), the Fundamental Research Funds for the Central Universities (Grant Nos. PA2020GDSK0077 and JZ2022HGPA0312), the National Key R&D Program of China (Grant No. JZ2022ZDYF0411), and the Opening Project of the Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University. The authors would acknowledge the Experimental Center of Engineering and Material Sciences at USTC for the fabrication and measurement of samples. The financial support to L. W. from the Research Grants Council of Hong Kong (GRF 17205421, 17204420, 17210319, 17204718, and CRF C1006-20WF) is gratefully acknowledged.
Publisher Copyright:
© 2023 Author(s).
PY - 2023/4/24
Y1 - 2023/4/24
N2 - Directed droplet manipulation is paramount in various applications, including chemical micro-reaction and biomedical analysis. The existing strategies include some kinds of gradients (structure, inherent wettability, and charge density), whereas they suffer from several limitations, such as low velocity, limited volume range, poor durability, and inefficient environmental suitability. Moreover, active bi-directional reversal of omni-droplets remains challenging because one kind of microstructure at a single scale cannot acquire two kinds of net results of mechanical interaction. Herein, we report an active and directional steering of omni-droplets utilizing bi-directional (vertical and horizontal) vibration on slippery cross-scale structures consisting of macro millimeter-scale circular arc arrays and micro/nanometer-scale slant ratchet arrays, which are fabricated by femtosecond laser patterned oblique etching and lubricant infusion. The physical mechanism of active droplet steering lies in the relative competition between the forces under vertical and horizontal vibration, which mainly arise from the circular arc arrays and slant ratchet arrays, respectively. Various steering modes, including climbing and programmable manipulation, can be realized. Our work is applicable to a wide range of potential applications, including circuit on/off and droplet-based chemical micro-reaction, particularly in the field of high-throughput omni-droplets operation.
AB - Directed droplet manipulation is paramount in various applications, including chemical micro-reaction and biomedical analysis. The existing strategies include some kinds of gradients (structure, inherent wettability, and charge density), whereas they suffer from several limitations, such as low velocity, limited volume range, poor durability, and inefficient environmental suitability. Moreover, active bi-directional reversal of omni-droplets remains challenging because one kind of microstructure at a single scale cannot acquire two kinds of net results of mechanical interaction. Herein, we report an active and directional steering of omni-droplets utilizing bi-directional (vertical and horizontal) vibration on slippery cross-scale structures consisting of macro millimeter-scale circular arc arrays and micro/nanometer-scale slant ratchet arrays, which are fabricated by femtosecond laser patterned oblique etching and lubricant infusion. The physical mechanism of active droplet steering lies in the relative competition between the forces under vertical and horizontal vibration, which mainly arise from the circular arc arrays and slant ratchet arrays, respectively. Various steering modes, including climbing and programmable manipulation, can be realized. Our work is applicable to a wide range of potential applications, including circuit on/off and droplet-based chemical micro-reaction, particularly in the field of high-throughput omni-droplets operation.
UR - http://www.scopus.com/inward/record.url?scp=85158171831&partnerID=8YFLogxK
U2 - 10.1063/5.0146217
DO - 10.1063/5.0146217
M3 - Journal article
AN - SCOPUS:85158171831
SN - 0003-6951
VL - 122
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 17
M1 - 174101
ER -