Haber Process Made Efficient by Hydroxylated Graphene: Ab Initio Thermochemistry and Reactive Molecular Dynamics

Vitaly V Chaban; Oleg V Prezhdo

doi:10.1021/acs.jpclett.6b01178

Haber Process Made Efficient by Hydroxylated Graphene: Ab Initio Thermochemistry and Reactive Molecular Dynamics

J Phys Chem Lett. 2016 Jul 7;7(13):2622-6. doi: 10.1021/acs.jpclett.6b01178. Epub 2016 Jun 28.

Authors

Vitaly V Chaban^{1

2}, Oleg V Prezhdo²

Affiliations

¹ Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo , 12231-280, São José dos Campos, SP, Brazil.
² Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States.

PMID: 27340901
DOI: 10.1021/acs.jpclett.6b01178

Abstract

The Haber-Bosch process is the main industrial method for producing ammonia from diatomic nitrogen and hydrogen. We use a combination of ab initio thermochemical analysis and reactive molecular dynamics to demonstrate that a significant increase in the ammonia production yield can be achieved using hydroxylated graphene and related species. Exploiting the polarity difference between N2/H2 and NH3, as well as the universal proton acceptor behavior of NH3, we demonstrate a strong shift of the equilibrium of the Haber-Bosch process toward ammonia (ca. 50 kJ mol(-1) enthalpy gain and ca. 60-70 kJ mol(-1) free energy gain). The modified process is of significant importance to the chemical industry.