Separated growth of Bi-Cu bimetallic electrocatalysts on defective copper foam for highly converting CO2 to formate with alkaline anion-exchange membrane beyond KHCO3 electrolyte

Luwei Peng, Yaofeng Wang, Yongxia Wang, Nengneng Xu, Wenshuang Lou, Peixuan Liu, Dongqing Cai, Haitao Huang, Jinli Qiao

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

Tuning the geometric and electronic structure of bimetallic electrocatalyst to facilitate a specific reaction pathway and offer more active sites is a promising avenue for enhancing activity and selectivity of electrocatalytic CO2 reduction reaction (eCO2RR). Owing to formation of Bi-Cu interface through the separated growth of Bi and Cu atoms on defective copper foam, the Bi-Cu bimetallic electrode converts CO2 to formate with an allured Faradaic efficiency (94.37%) and partial current density (27.85 mA cm−2) at -0.91 Vversus reversible hydrogen electrode (RHE). Notably, such electrode with tight moss-like structure delivers the excellent durability under 58 h electrolysis, outperforming most of the current Bi-based catalysts. Moreover, we have experimentally shown that KOH is a better electrolyte than KHCO3 due to the lower solution resistance and more confinement of free CO2 gas, and the alkaline anion-exchange membrane is more ideal than the cation-exchange membrane counterpart, owing to the enhancement of formate selectivity by suppressing the evolution of H2. This study inspires a complete set of concepts for highly converting CO2 to formate that contains the design of effective electrocatalysts, the role of growth substrate, the effect of different electrolytes and membranes.

Original languageEnglish
Article number120003
JournalApplied Catalysis B: Environmental
Volume288
DOIs
Publication statusPublished - 5 Jul 2021

Keywords

  • Alkaline anion-exchange membrane
  • Bi-Cu bimetallic electrode
  • Electrocatalytic CO reduction reaction
  • KOH and KHCO

ASJC Scopus subject areas

  • Catalysis
  • Environmental Science(all)
  • Process Chemistry and Technology

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