Tailored fiber placement-constructed bilayer basalt/cotton fabric for durable solar-driven interfacial evaporation

The escalating freshwater scarcity necessitates the development of highly efficient solar-driven interfacial evaporators. However, existing fabric-based evaporators still face challenges in long-term durability and salt management. Herein, we report a novel and durable candle soot-deposited basalt/cotton bilayer fabric evaporator (CBFE), constructed via tailored fiber placement (TFP) technology, followed by candle soot deposition and polydopamine (PDA) adhesion treatment. The CBFE features a unique core-sheath yarn design, where a hydrophilic cotton core ensures efficient water transport, and a basalt fiber sheath provides mechanical strength and a photothermal conversion substrate. TFP enables precise control over the fabric architecture, optimizing water supply and vapor escape. Carbon nanoparticles are introduced through candle soot deposition, with PDA enhancing their adhesion to the basalt fiber surface. Under 1 sun illumination, the CBFE achieves an evaporation rate of 1.5 kg·m −2 ·h −1 in 3.5 wt.% NaCl solution, demonstrating excellent cyclic stability and salt-resistant performance (maintaining 1.19 kg·m −2 ·h −1 in 20 wt.% NaCl solution). Outdoor tests and wastewater purification experiments (for methyl violet and rhodamine B) further confirm its high efficiency and versatility in practical applications. This work provides a new strategy for developing high-performance, long-lifespan solar evaporators, holding significant promise for sustainable freshwater production and environmental remediation.