Deposition and characterization of molybdenum oxide (MoO3) nanoparticles incorporated diamond-like carbon coatings using pulsed-DC PECVD

[Display omitted] •Incorporation of MoO3 nanoparticles into DLC using pulsed-DC PECVD.•The presence of Mo2C improved the adhesion property of the DLC-Mo thin film.•Rockwell C indentation test for DLC-Mo was classified as HF1 according to VDI 3198.•The minimum and maximum COF is 0.075 and 0.22 respectively. In this study a novel approach for the deposition of diamond-like carbon coating incorporated with molybdenum nanoparticles (DLC-Mo) thin film on tappet valve (metallic substrate) by incorporating MoO3 nanoparticles into DLC using pulsed-DC plasma enhanced chemical vapour deposition (PECVD) was successfully achieved. The as-deposited DLC-Mo was further characterized using scanning electron microscope/energy dispersive spectroscopy (SEM/EDS), X-ray diffraction (XRD), Raman spectroscopy, scratch test, Rockwell C indention test and nano-hardness measurement. The thickness was found to be 899.7 ± 16 nm. Hardness and elastic modulus 18.72 ± 0.1 and 150.03 ± 1.1 GPa respectively. The ID/IG was 0.98, D and G peaks positioned at 1350.92 and 1569.26 cm−1 respectively and Mo2C was observed from the XRD. The adhesion properties from the scratch and Rockwell C test were excellent, with low COF.