fig1
Figure 1. General NH3 synthesis processes. (A) H-B process: NH3 is prepared from H2 and N2 under high temperature (500 °C) and high pressure (20-50 MPa) over a Fe-based catalyst[18]; (B) Li-mediated three-step electrocatalytic cycling method for NH3 synthesis[11]; (C) Photocatalytic electron - excited N2 to NH3[13]; (D) Plasma directly dissociates N2 and then bonds with H+ to generate NH3[16]; (E) NH3 synthesis by PECP pathway. H-B: Haber-Bosch; PECP: plasma-electrocatalysis cascade pathway.
