Accelerating 1H NMR Detection of Aqueous Ammonia

Martin Kolen*, Wilson A. Smith, Fokko M. Mulder

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

5 Citations (Scopus)
62 Downloads (Pure)


Direct electrolytic N2 reduction to ammonia (NH3) is a renewable alternative to the Haber-Bosch process. The activity and selectivity of electrocatalysts are evaluated by measuring the amount of NH3 in the electrolyte. Quantitative 1H nuclear magnetic resonance (qNMR) detection reduces the bench time to analyze samples of NH3 (present in the assay as NH4+) compared to conventional spectrophotometric methods. However, many groups do not have access to an NMR spectrometer with sufficiently high sensitivity. We report that by adding 1 mM paramagnetic Gd3+ ions to the NMR sample, the required analysis time can be reduced by an order of magnitude such that fast NH4+ detection becomes accessible with a standard NMR spectrometer. Accurate, internally calibrated quantification is possible over a wide pH range.

Original languageEnglish
Pages (from-to)5698-5704
Number of pages7
JournalACS Omega
Issue number8
Publication statusPublished - 2021


Dive into the research topics of 'Accelerating 1H NMR Detection of Aqueous Ammonia'. Together they form a unique fingerprint.

Cite this