Ti atomdoped single vacancy silicene for hydrogen energy storage: DFT study

Hydrogen adsorption on titanium (Ti) atom–doped single vacancy silicene (SV‐SL) is investigated through first principles density functional theory (DFT) study. Strong hybridization of d‐orbitals of Ti atom to p‐orbitals of Si atoms results in a tight bond to the silicene sheet with energy of −6.48 eV and keeps away from metal clustering. Maximum 8 H2 molecules firmly bind to Ti atom–doped SV‐SL sheet with an adsorption energy ranging from −0.481 to −0.201 eV per H2 molecule and hydrogen storage capacity (HSC) of 6.3 wt%. Double‐side H2 adsorptions on hollow sites of Ti atom–doped SV‐SL sheet are verified by structural and electronic properties. The partial density of states (PDOS) analysis shows the kubas interaction mainly caused the molecular H2 adsorption. Further, the absence of spin‐up and spin‐down channels in electronic band structures of nH2 molecule adsorption to Ti atom–doped SV‐SL systems indicates its nonmagnetic nature. Conclusively, this study reveals that the Ti atom–doped SV‐SL can be a promising candidate for hydrogen storage applications. Hydrogen adsorption on titanium (Ti) atom–doped single vacancy silicene (SV‐SL) is investigated through density functional theory (DFT) study. Kubas interactions caused maximum 8 H2 molecules adsorption at ambient condition with adsorption energy −0.481 to −0.201 eV/H2 and hydrogen storage capacity (HSC) of 6.3 wt%.