Wood-based capillary enhancers for accelerated moisture capture and solar-powered release

Area of Science:

• Materials Science
• Environmental Science
• Chemical Engineering

Background:

• The global water crisis necessitates innovative solutions for water resource management.
• Atmospheric water harvesting presents a viable alternative water source.
• Liquid desiccants are effective for moisture capture but limited by slow adsorption/desorption.

Purpose of the Study:

• To enhance the adsorption and desorption dynamics of moisture capture using photothermal wood enhancers.
• To develop a cost-effective and scalable method for atmospheric water harvesting.

Main Methods:

• Fabrication of photothermal wood enhancers through partial delignification and low-temperature carbonization of balsa wood.
• Investigation of capillary transport and enlarged interfaces to improve moisture absorption and desorption.
• Quantification of moisture absorption and desorption rates under various relative humidity and temperature conditions.

Main Results:

• Moisture absorption rate increased by 103% (60% RH) and 84% (90% RH) within two hours.
• Desorption efficiency doubled, reaching 80% in two hours at 60°C.
• Solar-driven desorption achieved an evaporation rate of 1.217 kg·m⁻²·h⁻¹.

Conclusions:

• The photothermal wood enhancers effectively accelerate moisture absorption and desorption dynamics.
• This strategy enhances atmospheric water harvesting without altering the intrinsic properties of hygroscopic materials.
• The developed enhancers offer a promising approach for efficient and sustainable water generation from air.