Exploring perovskite oxide for advancing salt-resistant photothermal membranes and reliable thermoelectric generators

Abstract

Solar-driven water purification is a promising technology that efficiently exploits solar energy for water purification, desalination, and energy generation. However, poor material compliance requires intensive energy to generate vapors under natural sunlight with real-time practical implications. Therefore, advanced functional nanomaterials are highly desirable for reducing energy demand for water evaporation. Herein, we report bifunctional La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) perovskite oxide for solar-driven steam and thermoelectric generation. The hydrophilic/hydrophobic structure endows excellent salt-rejection, thermal management, and hydrophilic water channels for an efficient solar evaporation rate (2.36 kg m−2 h−1) using seawater (3.5 wt%) under 1 kW m−2 irradiation. More importantly, the salt-resistant and thermally insulated evaporation structure drives brine through milli-drilled water channels and re-dissolves back into the water body without impeding evaporation efficiency (16.83 kg m−2 mass change during 8 h under 1 sun irradiation). Besides, the LSCF-based photo-thermoelectric generator harvests solar energy into an electric output (Vout ∼ 292.2 mV, and Iout ∼ 52.5 mA). The state-of-the-art investigations and heat transfer simulations portray the device's functionality and its optimization toward long-term durability, thermoelectricity, and a suitable option for remote sensing areas.