Tailoring the lubricative and electroconductive bifunction properties of NbSe2 film by controlling the sputtering plasma

Abstract

Transition metal dichalcogenides are well known for their outstanding lubricating property. The special one of the family members, metallic NbSe2 film, was deposited by sputtering in this study. The microstructure, electrical conductivity and tribological properties of NbSe2 films were investigated by energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), grazing incidence X-ray diffraction (GIXRD), high resolution transmission electron microscopy (HRTEM), four-probe meter and ball-on-disk tribometer. The results showed that the microstructure of NbSe2 film could be tailored by simply controlling the sputtering power. The suitable power of 180 W promoted to crystal growth of NbSe2 film with edge plane orientation and formation of columnar structure, which possessed low static contact electrical resistivity and good adhesive strength on steel substrate. Both the dense and loose films made by lower and higher power, respectively, exhibited the downtrend of contact electroconductive and lubricative properties. The mechanism was discussed in terms of densification and crystallinity of films and transfer film formed on counterpart surface after sliding friction process. This novel NbSe2 film with low friction and dynamic contact electrical resistance behaviors was expected to a more feasible candidate for lubricative and electroconductive bifunctional material application.