Fig. 5: Spontaneous chlorine production.
From: Spontaneous chlorine production from chloride-containing brines
a Polarization curves (three-electrode configuration) showing the electrochemical performance: platinum (Pt) electrode in 0.01 M HCl (blue), platinum electrode in 0.5 M HCl (orange), and graphite electrode in 5 M HCl (light blue). Shadings represent the working electrode potential at a current density of 100 mA cm−2. Inset: schematic diagram of a three-electrode system. b Two-electrode polarization curve tested with graphite (anode) and Pt (cathode) electrodes. The shading shows a cell voltage of approximately 1.68 V at a current density of 100 mA cm−2. Inset: schematic diagram of a two-electrode system. c Faradaic efficiency of chlorine evolution reaction at various current densities. Error bars represent the standard deviation from four independent tests. d Optical image of the device composed of 18 serially connected power generation units for spontaneous chlorine and hydrogen production. e Linear correlation between total VOC and the number of units. Inset: schematic diagram for VOC measurement (f, g). Produced volume of H2 (f, orange circles) and Cl2 (g, blue line) in response to time. h Long-term stability test over seven days, showing robust current density (orange line) and hydrogen production rates (blue squares). i Comparison of electricity consumption and associated carbon emissions between our method (red, ~0 consumption and emissions) and traditional chlorine production methods. Source data are provided as a Source Data file.
