title: Atomic layer deposited molybdenum nitride thin film: a promising anode material for Li ion batteries.
abstract: Molybdenum nitride (MoNx) thin films are deposited by atomic layer deposition (ALD) using molybdenum hexacarbonyl [Mo(CO)6] and ammonia [NH3] at varied temperatures. A relatively narrow ALD temperature window is observed. In situ quartz crystal microbalance (QCM) measurements reveal the self-limiting growth nature of the deposition that is further verified with ex situ spectroscopic ellipsometry and X-ray reflectivity (XRR) measurements. A saturated growth rate of 2 Å/cycle at 170 °C is obtained. The deposition chemistry is studied by the in situ Fourier transform infrared spectroscopy (FTIR) that investigates the surface bound reactions during each half cycle. As deposited films are amorphous as observed from X-ray diffraction (XRD) and transmission electron microscopy electron diffraction (TEM ED) studies, which get converted to hexagonal-MoN upon annealing at 400 °C under NH3 atmosphere. As grown thin films are found to have notable potential as a carbon and binder free anode material in a Li ion battery. Under half-cell configuration, a stable discharge capacity of 700 mAh g(-1) was achieved after 100 charge-discharge cycles, at a current density of 100 μA cm(-2).
authors.affiliation: Department of Energy Science and Engineering, IIT Bombay , Mumbai, Maharashtra 400076, India.
authors.forename: Dip K
authors.initials: DK
authors.lastname: Nandi
authors.forename: Uttam K
authors.initials: UK
authors.lastname: Sen
authors.forename: Devika
authors.initials: D
authors.lastname: Choudhury
authors.forename: Sagar
authors.initials: S
authors.lastname: Mitra
authors.forename: Shaibal K
authors.initials: SK
authors.lastname: Sarkar