Renewable Syngas Generation via Low-Temperature Electrolysis: Opportunities and Challenges.

The production of syngas (i.e., a mixture of CO and H) via the electrochemical reduction of CO and water can contribute to the green transition of various industrial sectors.

Local hydrophobicity allows high-performance electrochemical carbon monoxide reduction to C products.

While CO can already be produced at industrially relevant current densities CO electrolysis, the selective formation of C products seems challenging. CO electrolysis, in principle, can overcome this barrier, hence forming valuable chemicals from CO in two steps. Here we demonstrate that a mass-produced, commercially available polymeric pore sealer can be used as a catalyst binder, ensuring high rate and selective CO reduction.

Systematic screening of gas diffusion layers for high performance CO electrolysis.

Certain industrially relevant performance metrics of CO electrolyzers have already been approached in recent years. The energy efficiency of CO electrolyzers, however, is yet to be improved, and the reasons behind performance fading must be uncovered. The performance of the electrolyzer cells is strongly affected by their components, among which the gas diffusion electrode is one of the most critical elements.

Intermittent Operation of CO Electrolyzers at Industrially Relevant Current Densities.

We demonstrate the dynamic operation of CO 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.

Morphological Attributes Govern Carbon Dioxide Reduction on N-Doped Carbon Electrodes.

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 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).