In-situ formation of bismuth nanoparticles on nickel foam for ambient ammonia synthesis via electrocatalytic nitrogen reduction

Guangzhe Li, Zhefei Pan, He Lin, Liang An

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

Bismuth has been regarded as a promising electrocatalyst for triggering nitrogen reduction to ammonia, due to the ease of nitrogen dissociation rendered by the strong interaction between Bi 6p band and the N 2p orbitals. However, the poor conductivity of bismuth limits the electron transfer for nitrogen reduction. In addition, the sluggish water dissociation on the bismuth surface leads to insufficient proton supply for the protonation step of *N2, causing inferior ammonia production performance. In this work, we prepare an integrated and binder-free bismuth nanoparticles@nickel foam electrode for ambient ammonia synthesis via a facile displacement reaction. Using nickel foam as the conductive substrate improves the electron transfer of bismuth for nitrogen reduction to ammonia. In addition, enhanced water dissociation on the nickel surface improves the protonation of *N2 by supplying adequate protons via hydrogen spillover, thus boosting the ammonia production performance. This integrated electrode eliminates the use of polymer binders and reduces the contact resistance between the diffusion layer and catalyst layer, facilitating electron delivery and reducing cell resistance, thus requiring less energy input for ammonia production. The performance examination in an electrochemical H-type cell shows that an ammonia yield rate as high as of 9.3 × 10−11 mol s−1 cm−2 and a Faradaic efficiency of 6.3% are achieved. An ammonia yield rate of 8.19 × 10−11 mol s−1 cm−2 is observed after 6 cycles, with a retention rate of 88%.

Original languageEnglish
Article number160006
JournalJournal of Alloys and Compounds
Volume875
DOIs
Publication statusPublished - 15 Sep 2021

Keywords

  • Ambient ammonia synthesis
  • Binder-free electrode
  • Bismuth nanoparticles
  • Electrocatalytic nitrogen reduction
  • In-situ formation
  • Nickel foam

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

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