Published December 26, 2023 | Version 1.0
Preprint Embargoed

High-Yield CO2 Electroreduction to Homogeneous Carbon Nanotubes

  • 1. Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, 117575, Singapore
  • 2. Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117585, Singapore
  • 3. Department of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai, 400019, India
  • 4. Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, 138634, Singapore

Description

The electrochemical CO2 reduction reaction (CO2RR) embodies a promising strategy to transform CO2 into fuels and chemical feedstocks. Nevertheless, these products may cause CO2 re-emission upon combustion,1,2 emphasizing the need for CO2-negative strategies to selectively transform CO2 into value-added products without re-emission. To this end, the molten salt CO2RR (MSCO2RR) enables CO2 transformation into solid-state nanostructured carbons,3-6 including valuable carbon nanotubes (CNTs). However, previous MSCO2RR-derived carbons, particularly CNTs, have exhibited non-uniform mixtures of carbon morphologies with low selectivity and graphitization degree, limiting applications and commercial viability. Here, we present an advancement: highly controllable Fe-catalyzed MSCO2RR-to-CNT growth in a molten Li2CO3 electrolyte, which yields highly homogeneous CNTs with good graphitization degree (~0.24 ID/IG) and high Faradaic efficiency (FE) exceeding 80%.

(See Preprint Main Text File for Additional Information)

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Embargoed

The files will be made publicly available on December 25, 2025.