Productivity and Selectivity of Gas‐Phase CO₂ Electroreduction to Methane at Copper Nanoparticle‐Based Electrodes

Abstract

In this study, copper nanoparticles are supported on porous carbon papers by airbrushing; they are then coupled with a Nafion 117 membrane to form working electrodes for the continuous production of methane through gas‐phase electroreduction of CO2 in a filter‐press electrochemical cell. The methane production and Faradaic efficiency (FE) are evaluated and compared at different applied voltages (from −1.8 to −2.4 V vs. Ag/AgCl) and catalyst loadings (0.25, 0.5, 1, and 1.5 mg cm−2). The maximum methane production rate is achieved at −2 V and 0.5 mg cm−2 (4.4 μmol m−2 s−1) whereas the highest Faradaic efficiencies can be obtained at 1 mg cm−2 (FE=10.1 %) and at −1.8 V (FE=12.1 %). The role of the porous carbon support and the possibility of humidifying the CO2 stream before it enters the cell are also tested. These results may provide a new understanding of the use of gas–liquid electrochemical membrane reactors for the direct conversion of CO2 in the gas phase.

A Core–Shell‐Structured Silver Nanowire/Nitrogen‐Doped Carbon Catalyst for Enhanced and Multifunctional Electrofixation of CO2

“…[5,[29][30][31] Through controlling field-induced reagent concentration, [5] metal-nitrogen-carbons tructure, [32] or partially oxidized atomicc obalt layers, [33] the CO 2 adsorptionc apacity of catalysts could be increased, whichs equentially resulted in CO 2 enrichment aroundc atalysts despite the low CO 2 solubility in the electrolyte, [21] which enhances the activity for CO 2 electroreduction.I no ur research, CO 2 adsorption measurements of all catalysts were investigated at2 98 K (Figure 4b). [5,[29][30][31] Through controlling field-induced reagent concentration, [5] metal-nitrogen-carbons tructure, [32] or partially oxidized atomicc obalt layers, [33] the CO 2 adsorptionc apacity of catalysts could be increased, whichs equentially resulted in CO 2 enrichment aroundc atalysts despite the low CO 2 solubility in the electrolyte, [21] which enhances the activity for CO 2 electroreduction.I no ur research, CO 2 adsorption measurements of all catalysts were investigated at2 98 K (Figure 4b).…”

“…Besides ECSA, the differencesb etween CO 2 adsorptionc apacity might also be an explanation for the enhanced electrocatalytic activity.A ccording to former reports, CO 2 electroreduction always suffers from slow kinetics, owing to the low local concentration of CO 2 around typical CO 2 reduction catalysts. [5,[29][30][31] Through controlling field-induced reagent concentration, [5] metal-nitrogen-carbons tructure, [32] or partially oxidized atomicc obalt layers, [33] the CO 2 adsorptionc apacity of catalysts could be increased, whichs equentially resulted in CO 2 enrichment aroundc atalysts despite the low CO 2 solubility in the electrolyte, [21] which enhances the activity for CO 2 electroreduction.I no ur research, CO 2 adsorption measurements of all catalysts were investigated at2 98 K (Figure 4b). For AgNW/NC700, the CO 2 adsorptionc apacity at 298 Ka nd 1bar is 59.1 cm 3 g À1 at standard temperaturea nd pressure (STP), larger than the 50.6 cm 3 g À1 at STP for AgNW/ NC800 and 43.1 cm 3 g À1 at STP for AgNW/NC600.…”

Tailoring gas-phase CO2 electroreduction selectivity to hydrocarbons at Cu nanoparticles

“…from -2.4 V to -1.8 V vs. Ag/AgCl) and catalytic loadings (i.e. from 0.25 mgcm -2 to 1.5 mgcm -2 ) in a MEA configuration [9]. The highest CH 4 production was achieved at 0.5 mgcm -2 and -2 V vs. Ag/AgCl (j=7.5 mAcm -2 ).…”

Highly Active, Durable Ultrathin MoTe2 Layers for the Electroreduction of CO2 to CH4

“…[4][5][6][7] Among the currently available materials, Cu-based catalysts have demonstrated promise for the catalysis of CO 2 to CH 4 . [8][9][10][11][12][13][14][15][16][17][18] However, high CH bond strength (434 kJ mol −1 ) and eight-electron transfer typically induce poor selectivity and a high applied potential for these catalysts, making it unrealistic to use these catalysts for practical applications. [13][14][15][16] Recently, transition-metal dichalcogenides (TMDs) have been attracting increasing attention for the electroreduction of CO 2 because of their unique layered structures.…”