ABSTRACT
The production of syngas (i.e., a mixture of CO and H2) via the electrochemical reduction of CO2 and water can contribute to the green transition of various industrial sectors. Here we provide a joint academic-industrial perspective on the key technical and economical differences of the concurrent (i.e., CO and H2 are generated in the same electrolyzer cell) and separated (i.e., CO and H2 are electrogenerated in different electrolyzers) production of syngas. Using a combination of literature analysis, experimental data, and techno-economic analysis, we demonstrate that the production of synthesis gas is notably less expensive if we operate a CO2 electrolyzer in a CO-selective mode and combine it with a separate PEM electrolyzer for H2 generation. We also conclude that by the further decrease of the cost of renewable electricity and the increase of CO2 emission taxes, such prepared renewable syngas will become cost competitive.
ABSTRACT
We demonstrate the dynamic operation of CO2 electrolyzer cells, with a power input mimicking the output of a solar photovoltaic power plant. The zero-gap design ensured efficient intermittent operation for a week, while avoiding significant performance loss.
ABSTRACT
The morphology of electrode materials is often overlooked when comparing different carbon-based electrocatalysts for carbon dioxide reduction. To investigate the role of morphological attributes, we studied polymer-derived, interconnected, N-doped carbon structures with uniformly sized meso or macropores, differing only in the pore size. We found that the carbon dioxide reduction selectivity (versus the hydrogen evolution reaction) increased around three times just by introducing the porosity into the carbon structure (with an optimal pore size of 27 nm). We attribute this change to alterations in the wetting and CO2 adsorption properties of the carbon catalysts. These insights offer a new platform to advance CO2 reduction performance by only morphological engineering of the electrocatalyst.
