Microgroove-Structured PDA/PEI/PPy@PI-MS Photothermal Aerogel with a Multilevel Water Transport Network for Highly...

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Solar-driven interfacial evaporation offers a sustainable solution for freshwater scarcity.
• Salt formation and crystallization hinder the long-term performance of solar evaporators.

Purpose of the Study:

• To develop a solar evaporator with enhanced salt-rejecting capability for stable operation in high-salinity conditions.
• To improve the long-term stability of solar evaporators by preventing salt crystallization.

Main Methods:

• Fabrication of a porous framework photothermal microgroove-structured aerogel (pppMGA) using freeze drying, laser engraving, and chemical polymerization.
• Construction of a multilevel water transport network including a 3D skeleton, microgroove channels, and a cotton core.
• Characterization of the aerogel's evaporation rate, photothermal conversion efficiency, and salt-rejecting performance.

Main Results:

• The pppMGA evaporator achieved a high evaporation rate of ~1.38 kg m⁻² h⁻¹ and photothermal conversion efficiency of ~93.04% under 1 sun illumination.
• Stable operation for 8 hours in 20% salt concentration water was demonstrated.
• The evaporator operated stably without salt crystallization even under 3 sun illumination and 20 wt% NaCl solution.

Conclusions:

• The developed pppMGA photothermal aerogel exhibits excellent salt-rejecting performance and long-term stability in high-salinity environments.
• This material provides a promising approach for designing efficient and stable interfacial evaporation systems for desalination.
• The multilevel water transport network and microgroove structure are key to enhancing salt rejection and preventing crystallization.