Enabling Electrocatalytic Fischer–Tropsch Synthesis from Carbon Dioxide Over Copper-based Electrodes

Abstract

We report on the discovery that paraffins and olefins up to C 6 hydrocarbons can be obtained in CO 2 electroreduction at room temperature and atmospheric pressure by application of a commercially available Cu-electrode (Eurofysica), provided pretreatment by electropolishing is avoided. The product distribution follows the Schultz-Flory distribution and, depending on the applied potential, the chain growth probability (α) ranges from 0.23 to 0.31, values lower than those obtained in Fischer-Tropsch synthesis over heterogeneous Co-or Fe-based catalysts.

Functioning devices for solar to fuel conversion

“…Recent results even show that for specific Cu electrodes Fischer-Tropsch distributions are encountered, see Fig. 4 [19]. The Faradaic efficiency is low, mainly because of the competing dissociation of water.…”

“…Two other major routes suggest themselves, for storing the collected photonic energy in the form of chemicals: -H 2 production by water splitting [11][12][13][14][15][16] -CO 2 reduction, combined with water oxidation (to O 2 ), yielding liquids such as alcohols or even hydrocarbons. This process is commonly referred to as artificial photosynthesis [17][18][19][20][21][22][23].…”

“…Scientific challenges in the domain of storing solar energy by CO 2 conversion are larger than for hydrogen synthesis. CO 2 conversion in the presence of water can lead to different products, such as methane or methanol, and little is known about the role of the chemical composition and surface structure of electrocatalytic and photo-catalytic converters in triggering selectivity [19][20][21][26][27][28][29]. In the following case studies we will further address the options for chemical storage of solar energy.…”

The Technical and Energetic Challenges of Separating (Photo)Electrochemical Carbon Dioxide Reduction Products

“…Nevertheless, some recent papers have identified potentially promising pathways (Qiao et al, 2014;Studt et al, 2014;Albo et al, 2015). Centi et al (2007) and Shibata et al (2008) have published tantalizing studies indicating that it is possible to produce C 4+ products electrochemically. Centi et al in particular even point to aromatics as a specific class of products produced.…”

“… EC CO 2 RR can only make C 1 -C 3 products with appreciable Faradaic efficiency (Section 2 of the Supplementary Information contains a list of all possible products), although a few studies have indicated the possible production of products with four or more carbon atoms (e.g., Centi et al, 2007;Shibata et al, 2008).  Certain C 1 products, such as CO and formate, can be made with high selectivity, but selectivity to C 2 products such as C 2 H 4 and/or ethanol remains poor.…”