Renewable Power for Electrocatalytic Generation of Syngas: Tuning the Syngas Ratio by Manipulating the Active Sites and System Design

Abstract

Achieving decarbonization through zero net CO2 emissions requires commercially viable application of waste CO2, throughout the transition to renewable and low‐carbon energy sources. A promising approach is the electrochemical carbon dioxide reduction reaction (CO2RR), which when powered with renewable electricity sources, provides a pathway for the conversion of intermittent renewable energy and waste CO2 into value‐added chemicals and fuels. However, as CO2RR is accompanied by the competing hydrogen evolution reaction (HER) due to the presence of water, an opportunity is presented to generate a mixture of CO and H2, also known as synthesis gas or syngas – the building block of various oxy‐hydrocarbon products. The aim of this review is to analyze both Power‐to‐CO and Power‐to‐Syngas studies, in order to classify and discuss the active sites for both CO and H2 generation through a new lens, providing insights into the structure‐activity correlations and facilitating the design of more active syngas electrocatalysts in the future. Through an evaluation of the economic viability of syngas generation, we determine that the carbon capture cost is a key parameter, with improvements in catalyst activity, catalyst impurity tolerance, and electrolyzer technology necessary for significant improvement in the economics of electrocatalytic syngas generation.

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

“…According to different techno-economic assessments (TEAs), electrochemical production of CO can already be profitable, if the technology is available at scale. ,, Furthermore, for applications where a steady supply of syngas is not needed, the electrochemical reduction of CO 2 provides a unique opportunity to convert intermittent but abundant renewable energy source into chemical fuels . What is equally important, different life cycle assessment (LCA) studies confirmed that such electrochemical routes can have a significant reduction in CO 2 footprint, compared to the traditional methods. , Meeting these three conditions together (i.e., economic viability, CO 2 footprint decrease, and large market size) predicts a great promise for electrochemical CO 2 -to-CO conversion.…”

Techno-Economic Analysis of Electrocatalytic CO2 Reduction into Methanol: A Comparative Study between Alkaline Flow Cell and Neutral Membrane Electrode Assembly

“…Alkaline flow cells and neutral membrane electrode assembly (MEA) are widely used as CO 2 electrolyzers in the literature [13][14][15]. They have the advantages of compact structure, high current density, low cell voltage, etc.…”