Engineered Wood with Hierarchically Tunable Microchannels toward Efficient Solar Vapor Generation

Area of Science:

• Materials Science
• Environmental Science
• Chemical Engineering

Background:

• Wood-based solar steam evaporators offer sustainable water purification.
• Engineering wood's internal porous structure is crucial but underexplored.
• Addressing water scarcity requires efficient and eco-friendly evaporation technologies.

Purpose of the Study:

• To fabricate a wood-based solar evaporator with hierarchical pores.
• To investigate the impact of engineered porous structures on solar vapor generation.
• To develop guidelines for high-performance solar steam generation devices.

Main Methods:

• Fabrication of a hierarchical porous structure within wood lumens using polyvinyl alcohol and ice-templating.
• Characterization of the engineered porous network, including pore size, surface area, and tortuosity.
• Performance evaluation of the polydopamine-coated polyvinyl alcohol-wood evaporator under solar irradiation.

Main Results:

• Engineered hierarchical pores with increased surface area and hydrophilicity.
• Achieved an evaporation rate of 1.6 kg m⁻² h⁻¹ under 1 sun irradiation.
• Demonstrated a high solar evaporation efficiency of 107%, surpassing most natural wood-based evaporators.

Conclusions:

• The polyvinyl alcohol-wood composite offers an inexpensive and sustainable solar evaporator.
• Hierarchical pore engineering significantly enhances solar steam generation performance.
• The study provides valuable insights for designing advanced solar steam generation devices.