Enhanced interfacial solar desalination using nano-engineered MoO _x photothermal evaporators

Area of Science:

• Materials Science
• Renewable Energy
• Chemical Engineering

Background:

• Interfacial solar desalination requires efficient light absorption, heat localization, and water management.
• Current limitations include low evaporation rates, processing difficulties, and poor material stability.

Purpose of the Study:

• To develop a novel solar absorber for enhanced interfacial solar desalination.
• To improve vaporization rates and material stability for commercial viability.

Main Methods:

• Fabrication of a substoichiometric molybdenum oxide (MoO_x) solar absorber with a nanochannel-on-microchannel architecture using Bessel laser beams.
• Characterization of optical absorbance, heat localization, and water management properties.
• Outdoor and indoor testing of solar desalination performance under varying solar intensities and water salinities.

Main Results:

• Achieved high evaporation rates: 4.21 kg m^-2 h^-1 (1 sun) and 19.3 kg m^-2 h^-1 (3 suns).
• Demonstrated superwicking capabilities and enhanced broadband absorbance.
• Identified that salt ions can enhance evaporation by reducing MoO_x-water contact.

Conclusions:

• The novel MoO_x absorber with hierarchical architecture significantly enhances solar desalination efficiency.
• The findings show great potential for large-scale solar desalination and advancing interfacial solar desalination technologies.