All-Day,\nAll-Weather Desalination Using a Contactless\nEvaporator with Antisalt Fouling Property

Interfacial\nsolar steam generation (ISSG) technology provides a\npromising solution to the global issue of freshwater scarcity. However,\nits practical application is hindered by salt fouling and inconsistent\nsolar illumination. In this work, a novel interfacial solar steam\ngenerator is proposed that integrates contactless design with low-voltage\njoule heating to provide all-day, all-weather freshwater generation.\nThe contactless design utilizes a solar-reduced graphene oxide coated\ncarbon fabric (SRGO–CF) as a heat generator and super hydrophilic\npaper walls as water transport channels. The contactless device can\ngenerate steam at the maximum rate of 4.27 kg m<sup>–2</sup> h<sup>–1</sup> under 1 sun solar illumination and small input\nvoltage due to the excellent photothermal and electrothermal capabilities\nof SRGO–CF. At an input voltage of 2.5 V, the SRGO–CF\nevaporator exhibits an evaporation rate of 3.52 kg m<sup>–2</sup> h<sup>–1</sup> and 2.32 kg m<sup>–2</sup> h<sup>–1</sup> for 3.5 wt % salt water respectively with and without 1 sun illumination\nfor a long period of time without any salt fouling, demonstrating\nits all-day, all-weather capability. The proposed contactless ISSG\nevaporator can resolve the impractical issue of conventional ISSG-based\nevaporators owing to irregular weather conditions and salt fouling\nissues while also promoting zero liquid discharge-based salt harvesting.