Low-Temperature Electrocatalytic Conversion of CO2 to Liquid Fuels: Effect of the Cu Particle Size

Abstract

A novel gas-phase electrocatalytic system based on a low-temperature proton exchange membrane (Sterion) was developed for the gas-phase electrocatalytic conversion of CO 2 to liquid fuels. This system achieved gas-phase electrocatalytic reduction of CO 2 at low temperatures (below 90 • C) over a Cu cathode by using water electrolysis-derived protons generated in-situ on an IrO 2 anode. Three Cu-based cathodes with varying metal particle sizes were prepared by supporting this metal on an activated carbon at three loadings (50, 20, and 10 wt %; 50% Cu-AC, 20% Cu-AC, and 10% Cu-AC, respectively). The cathodes were characterized by N 2 adsorption-desorption, temperature-programmed reduction (TPR), and X-ray diffraction (XRD) and their performance towards the electrocatalytic conversion of CO 2 was subsequently studied. The membrane electrode assembly (MEA) containing the cathode with the largest Cu particle size (50% Cu-AC, 40 nm) showed the highest CO 2 electrocatalytic activity per mole of Cu, with methyl formate being the main product. This higher electrocatalytic activity was attributed to the lower Cu-CO bonding strength over large Cu particles. Different product distributions were obtained over 20% Cu-AC and 10% Cu-AC, with acetaldehyde and methanol being the main reaction products, respectively. The CO 2 consumption rate increased with the applied current and reaction temperature.

Tuning the Catalytic Performance of Cobalt Nanoparticles by Tungsten Doping for Efficient and Selective Hydrogenation of Quinolines under Mild Conditions

“…Interestingly, the reduction profile of the catalyst containing tungsten doping species (CoW@C-0.05) is slightly shifted to lower temperatures, thus indicating that their presence influences the cobalt oxide reduction. Moreover, both catalysts display a broad H 2 -uptake peak centered at temperatures around 550–625 °C, which is typically associated with the gasification of carbon and the reduction of surface oxygenated groups present on the carbon surface. − In addition, for the catalyst CoW@C-0.05, a broad shoulder attributed to the reduction of tungsten oxide species can also be distinguished at higher temperatures between 700 and 800 °C . The H 2 -TPR profile of the catalyst CoW@C-0.25 is dominated by the presence of a peak associated with the reduction of Co 2+ species (at ∼330 °C) together with the broad peaks related to carbon and the reduction of tungsten oxide species.…”

Nanostructured Copper-Based Electrodes Electrochemically Synthesized on a Carbonaceous Gas Diffusion Membrane with Catalytic Activity for the Electroreduction of CO2

“…In particular, Cu-based electrode interfaces are able to stabilize the chemisorbed CO 2 · – radical anions and CO species, which are the key intermediates in the initial phase of the catalytic CO 2 conversion and in the subsequent process of hydrocarbon and alcohol formation, respectively. This not only increases the CO surface concentration, thereby promoting those CO 2 ER pathways involving C–C coupling reactions, but also blocks the reaction sites for the parasitic hydrogen evolution reaction (HER). , Recent studies concerning liquid-phase CO 2 ER have reported on the fundamental role of nano- and microstructures, − as well as the redox state , of Cu-based cathode materials in improving the catalyst’s selectivity and activity.…”

Emissions Control Catalysis

“…On the other hand, a major part of contributions (9/21) concerns original research on nitrogen oxides reduction processes [20][21][22][23][24][25][26][27][28], reflecting the fact that this topic still remains hot among the targets of environmental catalysis. Five out of 21 studies concern CO and hydrocarbons oxidation processes [29][30][31][32][33] while the remained 4/21 concern CO 2 capture/recycling processes under the view of cyclic economy [34][35][36][37].…”

“…De Lucas-Consuegra and co-workers [34] developed a low-temperature (below 90 • C) proton exchange membrane (Sterion) electrochemical cell for the electrocatalytic conversion of gaseous CO 2 to liquid fuels. This novel system achieved gas-phase electrocatalytic reduction of CO 2 over a Cu-based cathode by using water electrolysis-derived protons generated in-situ on an IrO 2 anode.…”