First-Principal Study of the Effect of Ti Doping on Hydrogenation of Mgn (N=2-8) Nanoclusters

Abstract

We report the effect of single Ti atom doping Mgn (n=2-8) clusters on hydrogenation kinetics using density functional theory (DFT). During growth process, variations of different energetic parameters, such as binding energy, stability, etc., with the size of the clusters, Mg4 and TiMg5, are found as thermodynamically stable. From chemisorption energies in hydrogenated Mgn and TiMgn clusters, we have estimated the catalytic effect of Ti doping in Mgn clusters to improve the dose of hydrogen. It is found that the activation barrier reduces by about 32.8% after Ti doping, as evident from the IRC study. ELF mapping indicates that the Ti doping increase the reactive sites in the Mg5 cluster, and the TiMg5 can absorb extra hydrogen molecule to attain the average binding energy of Mg5-2H. So, Ti doping in the Mg5 cluster improves the hydrogenation process as well as the dose concentration because of its catalytic activities