Voltage loss breakdown in desalination fuel cells

Desalination Fuel Cells with High Thermodynamic Energy Efficiency

“…The two-electron pathway leads to the formation of hydrogen peroxide (H 2 O 2 ) as a product (Table ), while the four-electron pathway leads to water (H 2 O) formation. The DFC tested here exhibits a significantly lower OCV than fuel cells, as also described in Abdalla et al, suggesting that the two-electron pathway is the dominant reaction occurring at the cathode . This is likely due to the chloride ions present in the catholyte channel, as it is known that these ions can poison Pt catalyst sites and shift the cathode reaction toward hydrogen peroxide formation. , …”

“…Given the desalination channel geometry and assuming 0.1 M NaCl concentration in this channel, we calculate the ionic resistance of this channel to be more than 1 order of magnitude smaller than the full cell resistance determined from the linear portion of the polarization curves (∼4 Ω). This also confirms what was measured experimentally by Abdalla et al recently, using reference electrodes inserted into the DFC channels, where it was shown that the voltage drop across reference electrodes placed in the anolyte and catholyte channels was typically <100 mV …”

“…Recently, the concept of fuel cells and the use of environmentally-friendly hydrogen to drive continuous water desalination and electricity generation within a single electrochemical cell have been established. ,, To our knowledge, Atlas et al first introduced this concept, termed the new cell as a desalination fuel cell (DFC), and characterized its thermodynamic energy efficiency (TEE), showing that the efficiency reached 68%. Zhang et al later characterized a DFC, showing a desalination rate of 18 g/m 2 /h for a 600 mM NaCl solution and electricity generation of 67 mW h/g of NaCl removed and termed it fuel-cell desalination.…”

“…The fuel cell elements include a fuel cell anode and cathode, while the cell also employs both an anion and cation exchange membranes as in an ED cell. Abdalla et al reported the first measured voltage loss breakdown of a DFC and showed that the cathode can be a major source of voltage losses, which was hypothesized to be due to poisoning of the Pt catalyst by chloride ions, while losses across membranes were typically negligible.…”

Finite-Time Thermodynamic Modeling and Analysis of Seawater Acidification Process in Electrochemical Acidification Cell

“…Dykstra et al [ 38 ] investigated the pH changes in electrochemical systems for the water desalination process. Abdalla et al [ 39 ] studied the voltage loss at the cathode, the anode, and across the membranes, respectively, in a desalination fuel cell. Khalla et al [ 40 ] investigated the available energy and electricity production of a desalination fuel cell under two operational modes.…”