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 H 2 molecules with a binding energy of −1.057eV/ H 2 ; and for the boron-doped CNT system, the binding energy of H 2 molecules increases to −1.151eV/ H 2 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 H 2 molecules implies that Ru decorated BCNT may be a useful and promising nanomaterial for hydrogen energy storage.