Stability and electronic properties of IrnV (n = 2–10) nanoclusters and their reactivity toward N2H4 molecule

DFT calculations have been carried out over the IrnV (n = 2–10) clusters in order to predict their stability, electronic, and catalytic properties. Based on the fragmentation energy (ΔEf) and the second-order difference energy (Δ2E), the results show that the V-doped iridium clusters with sizes of n = 5 and 7 were found more stable than their neighboring clusters. Our results also exhibit that the calculated energy gaps (Eg) for these clusters are in the range 0.074–0.603 eV, suggesting that the metallic character can manifest in these binary clusters. Therefore, the IrnV clusters can be utilized as catalysts in several catalytic reactions. MEP analysis exhibits that the highest positive charge resides on the V atom, thus the V atom in the binary clusters can be considered as the most active site for the nucleophilic attack. So, it represents a favorable electrophilic adsorption site that can strongly interact with the electron-rich molecules. The influence of the N2H4 adsorption over the electronic properties of IrnV clusters was also investigated. The results show that the adsorption energies (Eads) vary between − 21.3 and − 46.6 kcal mol−1, suggesting a chemisorption process. The change in enthalpy (ΔHads) is in the range of − 24.6 to − 51.0 kcal mol−1, indicating that the interaction between the IrnV clusters and the N2H4 molecule is very strong, and the formed complexes by chemisorption between the clusters and the N2H4 molecule are thermodynamically stable at standard conditions. The energy gaps of clusters are sharply changed upon adsorption of hydrazine onto the surface of the clusters, implying a great sensitivity of these clusters toward N2H4 molecule. The calculated dipole moments were also largely increased after chemisorption of the N2H4 molecule over the clusters.