Janus Wettability Grooved Structure for Convection-Enhanced Evaporation and Directional Salt Collection.

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Freshwater scarcity is a critical global issue.
• Solar-driven interfacial evaporation (SDIE) offers a sustainable solution.
• Vapor accumulation and salt deposition hinder SDIE efficiency.

Purpose of the Study:

• To develop an efficient solar evaporator overcoming SDIE limitations.
• To address vapor diffusion suppression and salt accumulation.
• To provide a novel design paradigm for evaporators.

Main Methods:

• Fabrication of a solar evaporator with a Janus wettability grooved structure.
• Evaluation of evaporation rates under varying conditions (natural and forced convection).
• Assessment of salt deposition behavior and long-term operational stability.

Main Results:

• The optimized Janus grooved evaporator achieved an evaporation rate of 2.27 kg m^-2 h^-1 under 1 sun.
• Under forced convection, the evaporation rate increased to 5.96 kg m^-2 h^-1.
• Stable operation for 30 h in 20 wt% brine with a salt collection rate of 193.9 g m^-2 h^-1 was demonstrated.

Conclusions:

• The Janus wettability grooved structure effectively enhances vapor diffusion and manages salt deposition.
• This design presents a significant advancement for efficient and sustainable SDIE.
• The study offers a practical paradigm for future solar evaporator development.