Approaches to electrodeposit molybdenum from ionic liquid

Abstract Molybdenum is a kind of refractory metal and can hardly be deposited in aqueous solution since it is more likely to form molybdenum oxide rather than elementary Mo, but molten salts and ionic liquid become alternative to obtain Mo layer. This paper shows an available process to obtain metallic state molybdenum deposit from ionic liquid. Mo layer was electrodeposited under constant current in ionic liquid 1‐Butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF 4 ). Micromorphology of the electrodeposited Mo layer was observed by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X‐ray photoelectron spectroscopy (XPS). Results show that elementary Mo layer was electrodeposited under constant current in ionic liquid BMIMBF 4 . Properties of the Mo layer are affected significantly by additive ethylene glycol (EG), deposition temperature and current density. By parallel tests taking into consideration of different technical factors, optimized process parameters are obtained as volume ratio of 2:1 in BMIMBF 4 + EG system, deposition temperature of 150 °C and current density of 0.75 mA·cm −2 .