Photo-Electro-Thermal Textiles for Scalable, High-Performance, and Salt-Resistant Solar-Driven Desalination.

ABSTRACT

Solar-driven interfacial evaporation is an emerging desalination technology that can potentially relieve the freshwater scarcity issue. To obtain high and continuous evaporation rates for all-weather, chemically engineered structural materials have been widely explored for simultaneous photothermal and electrothermal conversion. However, many previously reported fabrication processes involve poor integration and considerable energy loss. Herein, a scalable photo-electro-thermal textile is proposed to enable high efficiency, long-term salt rejection, and solar-driven desalination. Specifically, the photo-electro-thermal yarns with a core (commercial electric wire)-shell (polypyrrole-decorated Tencel) structure realize the integration of electrothermal and photothermal conversion. The wrapping eccentricity of 1.53 mm and pitch of 3 T cm-1 for the electric wire are rationally regulated to achieve a high surface temperature of over 52 °C at a 3 V DC input. As a result, exceptional and stable evaporation rates of 5.57 kg m-2 h-1 (pure water) and 4.89 kg m-2 h-1 (3.5 wt.% brine) under 1 kW m-2·radiation with a 3 V input voltage are realized. Practical application shows that the textiles can achieve high water collection of over 46 kg m-2 d-1 over the whole day of operation. The constructed photo-electro-thermal textile-based evaporator provides an effective method for commercial and scalable photo-electro-thermal conversion to achieve high-performance and salt-resistant solar-driven desalination.