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Droplet Transport in Two-Dimensional Channel Driven by Interlayer Distance-Induced Wettability Gradient
Mingyang Du1, Jiecheng Li1, Chenguang Yin1
1State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Department of Engineering Mechanics, School of Mechanics and Aerospace Engineering, Dalian University of Technology, Dalian116024, P. R. China.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 17, 2026
Summary
Wettability gradients on double-layer graphene nanochannels enable autonomous droplet transport. This study reveals optimal conditions for droplet movement, crucial for applications like drug delivery and microfluidics.
Area of Science:
- Nanofluidics
- Materials Science
- Surface Science
Background:
- Droplet transport in nanochannels is key for energy conversion, drug delivery, and nanofluidic applications.
- Wettability gradients offer an alternative to external fields for autonomous droplet manipulation.
Purpose of the Study:
- To investigate spontaneous and directional droplet transport in a 2D nanochannel with a wettability gradient.
- To identify optimal conditions for droplet migration by analyzing influencing factors.
Main Methods:
- Constructed a 2D nanochannel with a double-layer graphene wettability gradient.
- Employed numerical simulations to study droplet dynamics and transport mechanisms.
Main Results:
- Droplet motion is driven by the wettability gradient, exhibiting a two-stage acceleration-deceleration process.
- Increasing droplet size enhances transport in the small droplet regime.
- Optimized wettability and inclination angles promote migration, while channel height and interlayer distance can inhibit it.
Conclusions:
- Wettability gradient surfaces on 2D materials can achieve efficient autonomous droplet transport.
- Findings provide insights for designing advanced microfluidic devices and drug delivery systems.
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