A bifunctional electrochemical flow cell integrating ammonia production and electricity generation for renewable energy conversion and storage

Zhefei Pan, Yun Liu, Zhewei Zhang, Zhen Zhao, Jie Zhu, Rong Chen, Liang An

Research output: Journal article publicationJournal articleAcademic researchpeer-review

6 Citations (Scopus)

Abstract

Renewable energy has rapidly advanced in the global energy system, triggering the visible development of energy storage technologies in recent decades. Among them, the electricity-fuel-electricity approach is an effective way for the storage and utilization of renewable power. In this work, a bifunctional electrochemical flow cell integrating both ammonia production and electricity generation modes is developed for renewable energy conversion and storage. Ammonia, a hydrogen carrier having a high hydrogen content of 17.6 wt %, is relatively easier to convert to liquid phase for large-scale storage. The long-distance ammonia transport can reliably depend on the established infrastructure. In addition, as a carbon-free fuel beneficial for achieving the goal of carbon-neutrality, ammonia is considered as an environmentally benign and cost-effective mediator fuel. This flow cell is able to operate via two modes, i.e., an ammonia-production mode for energy storage in the form of ammonia (via nitrogen reduction reaction) and an electricity-generation mode for energy conversion in the form of electricity (via ammonia oxidation reaction). This flow cell is constituted by a PtAu/C-coated nickel-foam electrode for nitrogen and oxygen reduction reactions, a Pt/C-coated nickel-foam electrode for water and ammonia oxidation reactions, and an alkaline anion exchange membrane for charge-carrier migration. Charging this flow cell with the supply of nitrogen results in a Faradaic efficiency of 2.70% and an ammonia production rate as high as 9.34 × 10−10 mol s−1 cm−2 at 23 °C. Moreover, energizing this flow cell with ammonia results in an open-circuit voltage of 0.59 V and a peak power density of 3.31 mW cm−2 at 23 °C. A round-trip efficiency of 25.7% is realized with the constant-electrode mode.

Original languageEnglish
Pages (from-to)38361-38371
Number of pages11
JournalInternational Journal of Hydrogen Energy
Volume47
Issue number90
DOIs
Publication statusPublished - 9 Nov 2022

Keywords

  • Ammonia mediator
  • Electrochemical flow cell
  • Energy conversion and storage
  • Operation mode
  • Renewable energy

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Fuel Technology
  • Condensed Matter Physics
  • Energy Engineering and Power Technology

Fingerprint

Dive into the research topics of 'A bifunctional electrochemical flow cell integrating ammonia production and electricity generation for renewable energy conversion and storage'. Together they form a unique fingerprint.

Cite this