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Updated: Jun 25, 2026
07:32
Synthesis of Hydrogels with Antifouling Properties As Membranes for Water Purification
Published on: April 7, 2017
Ion Permeation in Zwitterionic Hydrogel for Stable Solar Desalination and Power Generation
Hongqi Zou1, Xiangtong Meng1, Jun Qi1
1State Key Laboratory of Organic-Inorganic Composites, State Key Laboratory of Chemical Resource Engineering, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, China.
Advanced Materials (Deerfield Beach, Fla.)
|June 23, 2026
Summary
This study introduces a zwitterionic hydrogel evaporator for efficient solar desalination. It prevents salt buildup and harnesses salinity gradients for power generation, offering a sustainable solution.
Area of Science:
- Materials Science
- Chemical Engineering
- Environmental Science
Background:
- Interfacial solar evaporation is promising for desalination but faces challenges with salt accumulation and inefficient use of salinity-gradient energy.
- Current salt rejection methods, primarily passive diffusion, are often ineffective in high-salinity conditions.
Purpose of the Study:
- To develop a novel zwitterionic hydrogel evaporator for efficient solar desalination.
- To address salt accumulation issues and utilize salinity-gradient energy for power generation.
Main Methods:
- Engineered a zwitterionic hydrogel evaporator with spatially separated channels for brine convection and ion permeation.
- Tested the evaporator's performance across various brine concentrations (0-25 wt.%).
- Validated the ion permeation mechanism using spectroscopy and simulations.
Main Results:
- Achieved high evaporation rates of 3.50 kg m-2 h-1 across diverse brines.
- Demonstrated no salt accumulation after 105 hours of continuous desalination in 3.5 wt.% brine.
- Leveraged the salinity gradient for power generation, achieving a record output of 24 W m-2.
Conclusions:
- The zwitterionic hydrogel evaporator effectively prevents salt accumulation through an ion permeation strategy.
- This approach enables synergistic utilization of brine resources and solar energy for desalination and power generation.
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