Efficient electrocatalytic conversion of carbon dioxide in a low-resistance pressurized alkaline electrolyzer

Jonathan P. Edwards, Yi Xu, Christine M. Gabardo, Cao Thang Dinh, Jun Li, Zhen Bang Qi, Adnan Ozden, Edward H. Sargent, David Sinton*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

72 Scopus citations

Abstract

Electrochemical carbon dioxide conversion offers a means to utilize carbon dioxide and simultaneously store excess renewable energy. To be economical, industrial carbon dioxide electroreduction systems require high energy efficiencies to minimize electrical input. To this end, these systems need high product selectivity at low cell voltages and industrially viable current densities. Here, a liquid phase flow cell electrolyzer using a silver catalyst for carbon dioxide conversion to carbon monoxide is reported. Significant improvements in cell efficiency are demonstrated through the synergistic combination of three factors: minimal electrode spacing (0.25 mm flow field), pressurization (50 bar), and alkalinity (5 M KOH). Diminished electrode spacings reduce ohmic losses, pressurization increases carbon monoxide selectivities, and alkaline conditions improve reaction kinetics. The combination of these three factors enables an uncorrected full cell energy efficiency of 67% at 202 mA/cm2, the highest reported above 150 mA/cm2. This system maintains a competitive energy efficiency of 47% at a high current density of 941 mA/cm2.

Original languageEnglish (US)
Article number114305
JournalApplied Energy
Volume261
DOIs
StatePublished - Mar 1 2020

Keywords

  • CO reduction reaction
  • CO utilization
  • Electrochemistry
  • Energy storage

ASJC Scopus subject areas

  • Building and Construction
  • Mechanical Engineering
  • General Energy
  • Management, Monitoring, Policy and Law

Fingerprint

Dive into the research topics of 'Efficient electrocatalytic conversion of carbon dioxide in a low-resistance pressurized alkaline electrolyzer'. Together they form a unique fingerprint.

Cite this