Stability and electronic properties of Rh-doped ruthenium clusters and their interaction with NH3 molecule

Abstract

The stability and electronic properties of the Rh-doped ruthenium clusters and their reactivity towards NH3 molecule have been studied using DFT calculations with the BLYP-D3/SDD level of theory. The results show that the doping of Ru clusters with Rh atom improves the catalytic performances of pure Ru clusters, and the Ru5Rh and Ru7Rh clusters are assumed to be less reactive than their neighbours. The interaction of NH3 with clusters exhibits that the Ru atoms are preferred adsorption sites for the NH3 molecule, and the adsorption takes place between the Ru atom of clusters and the N atom of NH3 molecule. The adsorption energies of NH3 on RunRh clusters are in the range of −101.5 to −218.4 kJ mol−1, suggesting a strong adsorption between both species. Upon adsorption process, the electronic properties of the Ru n Rh clusters were substantially changed. The variation of E g (ΔE g) for the Ru n Rh (n ≥ 7) clusters is very important (ΔE g ≥ 55%), suggesting that these clusters are very sensitive to the NH3 molecule. Hence, these clusters can be employed as nanosensors for the detection of the NH3 gas.