High-Efficiency Solar Desalination Accompanying ElectrocatalyticConversions of Desalted Chloride and Captured Carbon Dioxide

The sustainability of conventional water- and energy-associated systems is being examined in terms of water–energy nexus. This study presents a high-efficiency, off-grid solar desalination system for saline water (salinity 10 and 36 g L−1) that accompanies electrocatalytic oxidations of chloride and, consequently, urine via oxidized chlorine species, while concomitantly producing formate from captured CO2. A variable number of desalination cell arrays is placed between a double-layered nanoparticulate titania electrocatalyst (Ti/IrxTa1−xOy/nano-TiO2; denoted as n-TEC) anode and a porous dendrite Bi cathode. A potential bias to the n-TEC and Bi pair initiates the transport of chloride and sodium ions in the saline water to the anode and cathode cells, respectively, at an ion transport efficiency of ~100% and a specific energy consumption of ~1.9 kWh m−3. During the desalination, the n-TEC anode catalyzes the conversion of the transported chloride into reactive chlorine species, which in turn mediate the de...