Solar Interface Evaporation System Assisted by Mirror Reflection Heat Collection Based on Sunflower Chasing the Sun

Area of Science:

• Materials Science
• Renewable Energy
• Environmental Engineering

Background:

• Solar-driven water desalination is crucial for addressing global water scarcity.
• Developing efficient and cost-effective photothermal materials is key to advancing solar desalination technologies.

Purpose of the Study:

• To prepare and characterize a novel photothermal material, C-CP/MnO2, for efficient solar water evaporation and desalination.
• To investigate the material's structural properties and their influence on photothermal conversion and water transport.
• To evaluate the performance of the material in a solar desalination system, including its evaporation rate and efficiency.

Main Methods:

• Compounding corrugated paper (CP) with manganese dioxide (MnO2) to create the C-CP/MnO2 photothermal material.
• Characterization of the material's porous and semi-hollow structures and functional groups.
• Solar simulation experiments to measure evaporation rate and efficiency under 1 sun illumination.
• Zemax simulations to model light propagation and optimize heat collection.
• Design and testing of a sunflower-inspired solar tracking system for enhanced evaporation.

Main Results:

• The C-CP/MnO2 material exhibited excellent photothermal conversion efficiency due to its porous structure and oxygen-containing functional groups.
• The material demonstrated efficient water transport and rapid vapor escape, achieving an evaporation rate of 2.563 kg m⁻² h⁻¹ with 98.82% efficiency under 1 sun.
• Incorporation of a mirror heat collector increased the incident radiation by ~80%, boosting the evaporation rate to 4.314 kg m⁻² h⁻¹.
• The unique arch structure induced the Marangoni effect for continuous desalination of high-salinity brine.
• A solar tracking system significantly enhanced evaporation efficiency outdoors.

Conclusions:

• The C-CP/MnO2 composite is a highly efficient photothermal material for solar desalination.
• The material's structural design and the integration of advanced light-harvesting strategies significantly improve desalination performance.
• This study offers innovative approaches for solar interface evaporation and potential applications in industrial water treatment.