Advantages of CO over CO2 as reactant for electrochemical reduction to ethylene, ethanol and n-propanol on gas diffusion electrodes at high current densities

Hydrophobic thiol coatings to facilitate a triphasic interface for carbon dioxide reduction to ethylene at gas diffusion electrodes

“…Additionally, since the reduction of CO to C 2 H 4 follows the same mechanistic route as from CO 2 , trapping any CO that is released from two-electron CO 2 RR in the interface can facilitate its further reduction to increase the overall faradaic efficiency for C 2 H 4 . 22 To this end, surface coatings have proved to have a sizeable impact on the selectivity of even simple copper materials towards CO 2 RR to C 2 H 4 . Different coatings have been employed for different roles, such as adsorbed N-arylpyridinium additives to stabilise the adsorbed CO intermediates, 9 or polymers with intrinsic microporosity (PIMs) to conne gaseous reactants at the electrode surface.…”

CO2 Reduction to CO with 19% Efficiency in a Solar-Driven Gas Diffusion Electrode Flow Cell under Outdoor Solar Illumination

“…Transformation of solar energy into chemical bonds provides a long-term energy storage strategy that opens a path for the synthesis of fuels and chemicals . One approach to chemical energy storage is via solar-driven hydrogen generation, where (i) photovoltaics supply carbon-free electricity to the grid that is used to generate H 2 by water electrolysis at high current densities; (ii) photovoltaics are used to directly drive electrolysis at low current densities, or (iii) an integrated photoelectrochemical device performs unassisted direct water splitting to form H 2 . , Parallel to solar hydrogen generation approaches, pathways for solar-driven reduction of carbon dioxide to fuels have used (i) direct electrolysis, (ii) photovoltaic directly driven electrolysis, and (iii) integrated photoelectrochemical conversion. , Of particular interest is solar-driven reduction of carbon dioxide using a high-efficiency photovoltaic (PV) device directly coupled to an electrochemical cell tailored for reduction of CO 2 to CO. , Mixtures of solar-generated CO and H 2 could be used as syngas precursors in a future Fischer–Tropsch chemical synthesis process to produce high molecular weight hydrocarbon fuels or chemicals as products . Carbon dioxide reduction to CO is generally more energy efficient and kinetically easier than direct reduction of CO 2 to multicarbon products. ,, …”

Comparative Life Cycle Assessment of Electrochemical Upgrading of CO2 to Fuels and Feedstocks

“…CO electroreduction) can minimize overpotential and facilitate CO-CO dimerization, leading to increased single-pass conversion, 44 current density and selectivity (including C2H4, C2H5OH and C3H7OH). 21,22,45 The key performance parameters that govern the energetics of electrochemical conversion process are overpotential, and faradaic efficiency (FE), which defines the EE of the electrolyzer. On the other hand, single-pass CO2 conversion efficiency determines the energy cost of CO2 capture, and downstream product separation processes.…”

“…21 The two-step process can potentially reap multiple benefits, including mature SOEC with high stability, energy efficiency (~45% in first step 16 ), with high selectivity towards C2+ products in alkaline environment (in second step); overcoming challenges (i.e., low single-pass CO2 conversion due to carbonate formation) for one-step CO2 conversion to C2+ products. 21,22 All the processes mentioned herein signify diverse pathways and opportunities for alternative utilisation of CO2 to enable negative emission technology. 9,23 While recent studies [10][11][12][13] have highlighted some of the potential pathways for near-term deployment due to their technological maturity and economical feasibility over others, concerns remain on the climate benefits of these potential pathways.…”