open access publication

Preprint, 2024

The role of organic cations in the electrochemical reduction of CO2 in aprotic solvents

ChemRxiv, ISSN 2573-2293, 10.26434/chemrxiv-2024-wl1bg

Contributors

McGregor, Jon-Marc [1] Bender, Jay T 0000-0002-4511-8673 [1] Petersen, Amanda Schramm [2] Canada, Louise [1] Rossmeisl, Jan 0000-0001-7749-6567 [2] Brennecke, Joan [3] Resasco, Joaquin 0000-0001-6374-9877 [1]

Affiliations

  1. [1] The University of Texas at Austin
    2. [NORA names: United States; America, North; OECD];
  2. [2] University of Copenhagen
    3. [NORA names: KU University of Copenhagen; University; Denmark; Europe, EU; Nordic; OECD];
  3. [3] The University of Texas at

Abstract

The electrochemical reduction of CO2 is sensitive to the microenvironment surrounding catalytic active sites. Although the impact of changing electrolyte composition on CO2 reduction kinetics in aqueous electrolytes has been studied intensively, less is known about the influence of the electrochemical environment in non-aqueous solvents. Here, we present data demonstrating that organic alkyl ammonium cations influence catalytic performance in non-aqueous media and describe a physical model that rationalizes these observations. Using results from a combination of kinetic, spectroscopic, and computational techniques, we argue that the interfacial electric field present at the catalyst surface is sensitive to the molecular identity of the organic cation in the aprotic electrolyte. This is true irrespective of solvent, electrolyte ionic strength, or the supporting electrolyte counter anion. Our results suggest that changes in the interfacial field can be attributed to differences in the cation-electrode distance. Changes in the electric field strength are consequential to CO2R to CO as they modify the energetics of the kinetically relevant CO2 activation step.

Keywords

CO2, CO2 activation steps, CO2 reduction kinetics, CO2R, activation step, active site, anions, aprotic electrolytes, aprotic solvents, aqueous electrolyte, catalyst, catalyst surface, catalytic active sites, catalytic performance, cations, changes, combination, composition, computational techniques, counter anion, data, differences, distance, electric field, electric field strength, electrochemical environment, electrochemical reduction, electrochemical reduction of CO2, electrolyte, electrolyte composition, electrolyte ionic strength, energetics, environment, field, field strength, identity, impact, influence, interfacial electric field, interfacial field, ionic strength, kinetics, medium, microenvironment, model, molecular identity, non-aqueous media, non-aqueous solvents, observations, organic cations, performance, physical model, reduction kinetics, reduction of CO2, results, sites, solvent, steps, strength, surface, technique

Funders

  • Welch Foundation

Data Provider: Digital Science

LINKS
-

Matching Records in NORA

  • No Matches Found

SUBJECTS
+

METRICS
+