Hydrogen evolution reaction between small-sized Zrn (n=2-5) clusters and water based on density functional theory

Abstract

Abstract Density functional theory (DFT) was used to calculate the most stable structures of Zrn (n=2-5) clusters as well as the adsorption energies of Zrn (n=2-5) clusters after adsorbing single water molecule. The results reveal that there is a significant linear relationship between the adsorption energy and the energy gap of the Zrn (n=2-5) clusters. Furthermore, the calculation of the reaction paths between Zrn (n=2-5) and single water molecule shows that water molecule can react with Zrn (n=2-5) clusters to dissociate to produce hydrogen, and O atoms mix with the clusters to generate ZrnO (n=2-5), all of which are exothermic reactions. According to the released energy, the Zr4 cluster is the most efficient among Zrn (n=2-5) clusters reacting with single water molecule. The NPA and DOS demonstrate the production of hydrogen and orbital properties at different energy ranges, respectively, jointly forecasting that ZrnO (n = 2-5) will probably continue to react with more water molecules. Our findings contribute to better knowledge of Zr's chemical reactivity, which could aid in the development of effective Zr-based catalysts and hydrogen-production methods.