关键词: 玄武岩纤维, 织物组织, 光热蒸发性能, 结构调控, 海水淡化, 棉纱线, 复合织物, 光热材料

Abstract:

Objective This study addresses the poor processability and structural inflexibility of conventional photothermal materials by integrating basalt fibers (with high photothermal efficiency) with hydrophilic cotton yarns through weaving. Three fabric structures (plain, twill, satin) were engineered to optimize solar-driven interfacial evaporation (SDIE) performance, focusing on enhancing light absorption, water transport, and vapor release. The research highlights textile-based solutions for scalable and sustainable seawater desalination, offering a cost-effective alternative to energy-intensive methods like reverse osmosis.

Method Basalt fibers (98 tex) and cotton yarns (60 tex) were woven into plain fabric (PF), twill fabric (TF), and satin fabric (SF) using a semi-automatic loom. The warp density of all three fabrics was 50 roots/(10 cm), while the weft densities were 48, 44, and 40 roots/(10 cm), respectively. The SF featured extended weft floats (0.8-1.2 mm) to maximize basalt exposure. The post-machine cleaning of fabrics involved ultrasonic treatment with ethanol and water. Key analyses encompassed surface morphology (3-D microscopy), wettability (contact angle), light absorption (UV-Vis-NIR spectroscopy, 200-2 400 nm), evaporation rates under simulated sunlight (1-2 kW/m²), salt resistance (3.5%-15% NaCl), and water purification efficacy (ICP analysis).

Results Satin fabric (SF) exhibited superior performance achieving 94.5% photothermal efficiency and an evaporation rate of 1.59 kg/(m²·h) under 1.0 kW/m² by continuous basalt floats, outperforming PF (1.25 kg/(m²·h)) and TF (1.32 kg/(m²·h)). SF demonstrated near-linear scalability, reaching 2.74 kg/(m²·h) at 2.0 kW/m². In 15% NaCl, SF maintained an evaporation rate of 1.34 kg/(m²·h) (15% decline vs. freshwater), with less than 5% efficiency loss after 10 h in 5% NaCl. Post-treatment seawater showed 2-4 orders of magnitude reduction in Na⁺, Mg²⁺, Ca²⁺, and K⁺ concentrations, meeting standards. The condensate collection system achieved 98% salt rejection.

Conclusion Satin-woven basalt/cotton fabric represents a breakthrough in textile-based SDIE systems, synergizing light absorption, water supply, and vapor diffusion. Its structural design ensures high salt tolerance and scalability, enabling deployment in off-grid coastal regions. This work advances sustainable desalination by eliminating fossil fuel dependence and reducing costs. Future research should explore 3-D hybrid structures, integration with waste heat recovery, and real-world field validation to enhance practical applications in clean water production and renewable energy systems.

Key words: basalt fiber, fabric weave, photothermal evaporation property, structural control, desalination, cotton yarn, composite fabric, photothermal material