High carbonate ion conductance of a robust PiperION membrane allows industrial current density and conversion in a zero-gap carbon dioxide electrolyzer cell

Abstract

The poly(aryl piperidinium)-based anion exchange membrane (PiperION) with high carbonate conductance is employed for CO2 electrolysis to CO in conjunction with a tailored electrolyzer cell structure. This combination results in...

Operando cathode activation with alkali metal cations for high current density operation of water-fed zero-gap carbon dioxide electrolysers

“…7b), which is a measure of the derivative of the current-voltage curve. In contrast, the high frequency limits do not differ much, being around 1 Ω cm 2 for both, which is comparable with the values reported for similar systems 10,27 . This value is related to the total cell resistance, including the membrane, the contribution of which to the total impedance spectra was found to be ohmic in our control experiments (Supplementary Note 2 and Supplementary Fig.…”

“…The design of this cell is very similar to its smaller counterpart, but instead of being spherical, it is rectangular in shape. A stack containing three cells was connected in series electrically and in parallel with regards to gas distribution 10,24 .…”

“…Consequently, AEM-based operation should be independent of whether an alkaline solution or pure water is fed to the anode (given that the anode catalyst functions in both media). Still, in contrast to the wealth of alkaline studies 10,[22][23][24][25][26] , to the best of our knowledge, there is no study in the literature where a zero-gap electrolyser cell with a commercial membrane is operated with water anolyte at high CO 2 R current. In one single study, high current density was ensured using an experimental membrane 27 .…”

“…For industrialization, however, several requirements must be fulfilled simultaneously, such as operation at high current density (j), high energy efficiency (EE), high product selectivity (Faradaic efficiency, FE), and long-term stability 6 , 7 . Besides the catalysts, 8 , 9 electrolyzer cell design is equally important in determining these parameters 10 .…”

Electrolytic Conversion of Bicarbonate Solutions to CO at >500 mA cm-2 and 2.2 V

“…A commercial CO2RR electrolyzer will likely need to operate at current densities ( J ) greater than 200 mA cm -2 and cell voltages ( V cell ) below 3 V [5][6][7][8] . The highest-performing CO2RR lab-scale electrolyzers are now capable of meeting these criteria when a pure gaseous CO 2 feedstock is used [9][10][11][12][13][14] .…”