1
|
Liu Y, Peng X, Zhu L, Jiang R, Liu J, Chen C. Liquid-Assisted Bionic Conical Needle for In-Air and In-Oil-Water Droplet Ultrafast Unidirectional Transportation and Efficient Fog Harvesting. ACS APPLIED MATERIALS & INTERFACES 2023; 15:59920-59930. [PMID: 38100412 DOI: 10.1021/acsami.3c14713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Learning from nature, many bionic materials and surfaces have been developed for the directional transportation of water and fog collection. However, current research mainly focuses on the self-transportation behavior of droplets in air-phase environments, rarely concerning underoil environments. Herein, in this work, a liquid-assisted bionic copper needle was fabricated for the rapid self-transportation of water droplets in air and oil environments. The water droplet can be spontaneously transported on the as-prepared bionic copper needle from the tip to the base. More importantly, the water-prewetted bionic copper needle can achieve the ultrafast unidirectional transportation of a water droplet in an oil environment, showing a maximum transport velocity of 76.2 mm/s and a transport distance over 33 mm, which were ten times higher than those reported in the previous research. Additionally, the droplet transport mechanism was revealed. The effects of the apex angle and tilt angle of the as-prepared bionic needle and droplet volume on the self-transportation behavior of water droplets were systematically investigated. The results indicated that the transport velocity of the water droplet decreased with the increase of the apex angle of the conical needle, while it increased with the increase of the droplet volume and needle tilt angle. Furthermore, the as-prepared bionic copper needle exhibited excellent fog collection performance with a single copper needle fog collecting efficiency of up to 2220 mg/h, which was 9.7 times that of the original copper needle. In summary, this work provides a simple and novel method to fabricate bionic copper needles for the directional self-transportation of water droplets in air-phase and oil-phase environments as well as efficient fog collection. It shows great application potential in the fields of microfluidics, desalination, and freshwater collection.
Collapse
Affiliation(s)
- Yangkai Liu
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
| | - Xuqiao Peng
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
| | - Linfeng Zhu
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
| | - Ruisong Jiang
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
| | - Jian Liu
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
| | - Chaolang Chen
- School of Mechanical Engineering, Sichuan University, Chengdu 610065, China
- National United Engineering Laboratory for Advanced Bearing Tribology, Henan University of Science and Technology, Luoyang 471023, China
| |
Collapse
|
2
|
Tang C, Zhu Y, Bai H, Li G, Liu J, Wu W, Yang Y, Xuan S, Yin H, Chen Z, Lai L, Song Y, Cao M, Qiu B. Spontaneous Separation of Immiscible Organic Droplets on Asymmetric Wedge Channels with Hierarchical Microchannels. ACS APPLIED MATERIALS & INTERFACES 2023; 15:49762-49773. [PMID: 37843979 DOI: 10.1021/acsami.3c10211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Spontaneous separation of immiscible organic droplets has substantial research implications for environmental protection and resource regeneration. Compared to the widely explored separation of oil-water mixtures, there are fewer reports on separating mixed organic droplets on open surfaces due to the low surface tension differences. Efficient separation of mixed organic liquids by exploiting the rapid spontaneous transport of droplets on open surfaces remains a challenge. Here, through the fusion of inspiration from the fast droplet transport capability of Sarracenia trichome and the asymmetric wedge channel structure of shorebird beaks, this work proposes a spine with hierarchical microchannels and wedge channels (SHMW). Due to the synergistic effect of capillary force and asymmetric Laplace force, the SHMW can rapidly separate mixed organic droplets into two pure phases without requiring additional energy. In particular, the self-spreading of the oil solution on the open channel surface is utilized to amplify the surface energy difference between two droplets, and SHMW achieves the pickup of oil droplets floating on the surface of the organic solution. The maximum separation efficiency on 3-SHMW can reach 99.63%, and it can also realize the antigravity separation of mixed organic droplets with a surface tension difference as low as 0.87 mN·m-1. Furthermore, SHMW performs controllable separation, oil droplet pickup, and continuous separation and collection of mixed organic droplets. It is expected that this cooperative structure composed of hierarchical microchannels and wedge channels will be realized in resource recovery or chemical reactions in industrial production processes.
Collapse
Affiliation(s)
- Chengning Tang
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Yuying Zhu
- Center for Biomedical Imaging, University of Science and Technology of China, Hefei 230027, Anhui, P. R. China
| | - Haoyu Bai
- School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University, Tianjin 300350, China
| | - Guoqiang Li
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Jiasong Liu
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Weiming Wu
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Yi Yang
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Sensen Xuan
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Huan Yin
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Zuqiao Chen
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Lin Lai
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Yuegan Song
- School of Manufacture Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, P. R. China
| | - Moyuan Cao
- School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University, Tianjin 300350, China
| | - Bensheng Qiu
- Center for Biomedical Imaging, University of Science and Technology of China, Hefei 230027, Anhui, P. R. China
| |
Collapse
|
3
|
Zhang K, Xiang W, Liu J, Xie Z. Flexible droplet transportation and coalescence via controllable thermal fields. Anal Chim Acta 2023; 1277:341669. [PMID: 37604623 DOI: 10.1016/j.aca.2023.341669] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/03/2023] [Accepted: 07/26/2023] [Indexed: 08/23/2023]
Abstract
Flexible droplet transportation and coalescence are significant for lots of applications such as material synthesis and analytical detection. Herein, we present an effective method for controllable droplet transportation and coalescence via thermal fields. The device used for droplet manipulation is composed of a glass substrate with indium tin oxide-made microheaers and a microchannel with two transport branches and a central chamber, and it's manipulated by sequentially powering the microheaters located at the bottom of microchannel. The fluid will be unevenly heated when the microheater is actuated, leading to the formation of thermal buoyancy convection and the decrease of interfacial tension of fluids. Subsequently, the microdroplets can be transported from the inlets of microchannel to the target position by the buoyancy flow-induced Stokes drag. And the droplet migration velocity can be flexibly adjusted by changing the voltage applied on the microheater. After being transported to the center of central chamber, the coalescence behaviors of microdroplets can be triggered if the microheater located at the bottom of central chamber is continuously actuated. The droplet coalescence is the combined effect of decreased fluid interfacial tension, the shortened droplet distance by buoyancy flow and the increased instability of droplet under the elevated temperature. The droplet coalescence efficiency is also related to the voltage of microheater, by increasing the voltage from 3.5 V to 7 V, the needed time for droplet coalescence dramatically decrease from 220s to 1.4 s. Finally, by the droplet coalescence-triggered calcium hydroxide precipitation reaction, we demonstrate the applicability of the droplet manipulation method on specific sample detection. Therefore, this approach used for droplet transportation and coalescence can be attractive for many droplet-based applications such as analytical detection.
Collapse
Affiliation(s)
- Kailiang Zhang
- College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin, 150001, PR China
| | - Wei Xiang
- College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin, 150001, PR China
| | - Jiuqing Liu
- College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin, 150001, PR China
| | - Zhijie Xie
- College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin, 150001, PR China.
| |
Collapse
|