First-principles study of hydrogen storage over Ni and Rh doped BN sheets

TL;DR

This study uses first-principles calculations to explore hydrogen absorption on Ni and Rh doped BN sheets, revealing stable metal sites, absorption mechanisms, and bonding nature, which could inform hydrogen storage material design.

Contribution

It provides detailed insights into hydrogen adsorption mechanisms and bonding on Ni and Rh doped BN sheets using first-principles methods, highlighting the potential for hydrogen storage applications.

Findings

Ni prefers nitrogen top sites, Rh prefers hollow sites.

Rh dissociates hydrogen molecules, Ni absorbs them molecularly.

Both metals can absorb up to three hydrogen molecules.

Abstract

Absorption of hydrogen molecules on Nickel and Rhodium doped hexagonal boron nitride(BN) sheet is investigated by using the first principle method. The most stable site for the Ni atom was the on top side of nitrogen atom, while Rh atoms deservers a hollow site over the hexagonal BN sheet. The first hydrogen molecule was absorbed dissociatively over Rh atom, and molecularly on Ni doped BN sheet. Both Ni and Rh atoms are capable to absorb up to three hydrogen molecules chemically and the metal atom to BN sheet distance increases with the increase in the number of hydrogen molecules. Finally, our calculations offer explanation for the nature of bonding between the metal atom and the hydrogen molecules, which is due to the hybridization of metal d orbital with the hydrogen s orbital. These calculation results can be useful to understand the nature of interaction between the doped metal and the BN sheet, and their interaction with the hydrogen molecules.