The Haber-Bosch (HB) process, critical for global ammonia production, is hindered by its high energy consumption and operational demands, requiring extreme pressures and temperatures. Developing catalysts that reduce these demands while maintaining practical efficiency is essential for achieving sustainable ammonia synthesis. Here, we investigate the FeCoNi(AlSi)0.76 high-entropy alloy (HEA) as a catalyst for the HB process using quantum mechanics (QM) and kinetic Monte Carlo (kMC) simulations. Mechanistic analysis revealed significantly lower reaction barriers compared to pure Fe, and kMC simulations predict an NH3 turnover frequency (TOF) that is 65 times higher than pure Fe under industrial conditions. Under reduced pressure (21 atm) and moderate temperature condition (673 K), the HEA retained half the NH3 production rate of pure Fe at extreme industrial conditions, revealing its potential to reduce energy and pressure requirements. This study demonstrates the promise of HEAs in enabling more energy-efficient and sustainable ammonia production technologies.

Revolutionizing Ammonia Synthesis: FeCoNiAlSi High-Entropy Alloy Catalyst for Low-Pressure, Low-Temperature Applications

Sementa, Luca;Fortunelli, Alessandro;
2025

Abstract

The Haber-Bosch (HB) process, critical for global ammonia production, is hindered by its high energy consumption and operational demands, requiring extreme pressures and temperatures. Developing catalysts that reduce these demands while maintaining practical efficiency is essential for achieving sustainable ammonia synthesis. Here, we investigate the FeCoNi(AlSi)0.76 high-entropy alloy (HEA) as a catalyst for the HB process using quantum mechanics (QM) and kinetic Monte Carlo (kMC) simulations. Mechanistic analysis revealed significantly lower reaction barriers compared to pure Fe, and kMC simulations predict an NH3 turnover frequency (TOF) that is 65 times higher than pure Fe under industrial conditions. Under reduced pressure (21 atm) and moderate temperature condition (673 K), the HEA retained half the NH3 production rate of pure Fe at extreme industrial conditions, revealing its potential to reduce energy and pressure requirements. This study demonstrates the promise of HEAs in enabling more energy-efficient and sustainable ammonia production technologies.
2025
Istituto di Chimica dei Composti Organo Metallici - ICCOM - Sede Secondaria Pisa
Istituto per i Processi Chimico-Fisici - IPCF - Sede Secondaria Pisa
Alloy catalyst; Ammonia production; Ammonia synthesis; Haber-Bosch process; High entropy alloys; Industrial conditions; Kinetic monte carlo simulation;
File in questo prodotto:
File Dimensione Formato  
ja5c00606_si_001.pdf

accesso aperto

Descrizione: supporting information
Tipologia: Altro materiale allegato
Licenza: Altro tipo di licenza
Dimensione 1.97 MB
Formato Adobe PDF
1.97 MB Adobe PDF Visualizza/Apri
HB-HEA-Ms-final.pdf

embargo fino al 15/04/2026

Descrizione: “This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, copyright © 2025 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/jacs.5c00606.”
Tipologia: Documento in Post-print
Licenza: Altro tipo di licenza
Dimensione 949.49 kB
Formato Adobe PDF
949.49 kB Adobe PDF   Visualizza/Apri   Richiedi una copia
J. Am. Chem. Soc. 2025, 147, 17, 14541–14553.pdf

solo utenti autorizzati

Tipologia: Versione Editoriale (PDF)
Licenza: NON PUBBLICO - Accesso privato/ristretto
Dimensione 5.63 MB
Formato Adobe PDF
5.63 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14243/542764
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? ND
social impact