# The Haber Process Made Efficient by Hydroxylated Graphene

**Authors:** Vitaly Chaban, Oleg Prezhdo  
**arXiv:** [1603.08041](https://arxiv.org/abs/1603.08041)  
**Date:** 2016-03-25  
**Summary page:** https://www.summarizepaper.com/en/paper/1603.08041v1/

## Key points

- The Haber-Bosch process is the primary industrial method for producing ammonia from diatomic nitrogen and hydrogen
- The process requires an iron catalyst, high temperature, and pressure which makes it highly demanding energetically
- Any improvement to the Haber process would have a significant scientific and economic impact
- A recent study by Vitaly Chaban and Oleg Prezhdo reports a substantial increase in ammonia production using hydroxylated graphene
- Hydroxylated graphene provides the polar environment favoring the forward reaction while remaining stable under investigated thermodynamic conditions
- Their research shows that ca. 50 kJ mol-1 enthalpy gain and ca. 60-70 kJ mol-1 free energy gain are achieved at temperatures ranging from 298 to 1300 K and pressures ranging from 1 to 1000 bar
- This shift in reaction equilibrium towards the product strongly increases reaction yield while decreasing temperature and pressure requirements, thereby reducing costs associated with production
- Electronic structure calculations and real-time reactive simulations provide a clear microscopic interpretation of this observed phenomenon
- The demonstrated principle can be applied with many polar groups functionalizing a substrate with high surface area provided that it is chemically inert to H2, N2, and NH3
- Overall, this modified Haber-Bosch process has significant importance to the chemical industry since it substantially increases reaction yield while decreasing costs through lower temperature and pressure requirements compared to traditional methods of ammonia production

## Summary

The Haber-Bosch process is the primary industrial method for producing ammonia from diatomic nitrogen and hydrogen. However, this process is highly demanding energetically, requiring an iron catalyst, high temperature, and pressure. Any improvement to the Haber process would have a significant scientific and economic impact. In a recent study by Vitaly Chaban and Oleg Prezhdo, they report a substantial increase in ammonia production using hydroxylated graphene. By exploiting the polarity difference between N2/H2 and NH3, as well as the universal proton acceptor behavior of NH3, Chaban and Prezhdo demonstrate a strong shift of the equilibrium of the Haber-Bosch process towards ammonia. Hydroxylated graphene provides the polar environment favoring the forward reaction while remaining stable under investigated thermodynamic conditions. Their research shows that ca. 50 kJ mol-1 enthalpy gain and ca. 60-70 kJ mol-1 free energy gain are achieved at temperatures ranging from 298 to 1300 K and pressures ranging from 1 to 1000 bar. This shift in reaction equilibrium towards the product strongly increases reaction yield while decreasing temperature and pressure requirements, thereby reducing costs associated with production. Electronic structure calculations and real-time reactive simulations provide a clear microscopic interpretation of this observed phenomenon. The demonstrated principle can be applied with many polar groups functionalizing a substrate with high surface area provided that it is chemically inert to H2, N2, and NH3. Overall, this modified Haber-Bosch process has significant importance to the chemical industry since it substantially increases reaction yield while decreasing costs through lower temperature and pressure requirements compared to traditional methods of ammonia production.