Ruthenium decorated boron-doped carbon nanotube for hydrogen storage: A first-principle study

Abstract

In this paper, the adsorption of molecular hydrogen on Ruthenium (Ru) decorated boron-doped single-walled carbon nanotube (CNT) is theoretically studied, based on the density-functional theory (DFT). The projected density of states (PDOS) and charge density difference are computed, and Mulliken population analysis is conducted to investigate the molecular hydrogen adsorption ability of a boron-doped CNT (BCNT) system and a pure CNT system. As for the pure CNT system, a single Ru atom can absorb up to four H2 molecules with a binding energy of −1.057eV/H2; and for the boron-doped CNT system, the binding energy of H2 molecules increases to −1.151eV/H2 and it displays much higher binding energy of Ru with the increase of 21.19%. This implies that the BCNT system is more stable and has better ability to adsorb hydrogen molecules. The enhanced ability to adsorb H2 molecules implies that Ru decorated BCNT may be a useful and promising nanomaterial for hydrogen energy storage.