Mechanism research reveals the role of Fe n ( n = 2-5) supported C 2 N as single-cluster catalysts (SCCs) for the non-oxidative propane dehydrogenation in the optimization of catalytic performance.

Single cluster catalysts show excellent potential for propane dehydrogenation, compensating for the limited catalytic performance of single-atom catalysts in reactions involving multiple reaction steps and intermediates. Herein, density functional theory is used to investigate the catalytic activity and mechanism for non-oxidized propane dehydrogenation on Fe n -C 2 N ( n = 2-5). Firstly, the stability of Fe n -C 2 N ( n = 2-5) is evaluated by comparing the mean values of binding energy and cohesive energy. The results show that Fe n -C 2 N ( n = 2-4) can exist stably, which is also verified by the molecular dynamics calculation at 873 K. Band structure analysis shows that the screened catalysts have metal properties, which are conducive to charge transfer. Fukui function analysis is used to predict the optimal adsorption site. The electronic properties of propane and propylene adsorbed on catalysts are further studied by the partial density of states and deformation charge density. The activation barrier ( E a ) and reaction energy (Δ E ) of the main reaction steps are evaluated. The results show that Fe 2 -C 2 N ( E a = 0.97 eV, Δ E = 0.22 eV) has the best catalytic activity. The E a for further propylene dehydrogenation is also used to evaluate the yield of propylene. Compared with Fe-C 2 N, Fe 2 -C 2 N can regulate the adsorption strength of propane and propylene, showing better catalytic ability and higher selectivity for propylene. The above research provides ideas for the design of new catalysts with high selectivity and activity for non-oxidative propane dehydrogenation.