Atomic layer deposition of nitrogen incorporated molybdenum oxide: Unveiling carrier transport mechanism and its application in Li-ion battery

Nitrogen incorporated molybdenum oxide (MoO_x:N) thin films are obtained by stacking of atomic layer deposited grown MoO_x and MoN_x in a nanolaminate architecture without any postdeposition processing. Evolution of stoichiometrically dependent electron conductivity is obtained that is efficiently controlled by varying the ratio of the number of layers (MoO_x to MoN_x) in the nanolaminate structure. The carrier type, the free carrier concentration, and the mobility of the as-grown materials are studied by temperature-dependent Hall-effect measurement. The authors hypothesize that the addition of N-atom creates oxygen vacancies in the films that in turn act as a shallow donor level that results in improved conductivity in the ternary material. As-grown materials, both in the form of planar architecture and coaxially grown on multiwalled carbon nanotubes are investigated as a prospective anode material in the Li-ion battery. The comparison reveals a substantially improved performance of N-incorporated samples than that of the pristine materials. The highest discharge capacity of 1287 mA h g⁻¹ was achieved in the first cycle at a current rate of 0.1 A g⁻¹, and a stable capacity of 974 and 610 mA h g⁻¹ is achieved when discharged at 0.1 and 2 A g⁻¹, respectively, from the core-shell structures.