Lubricity performance of hydrogen-free CVD growth of graphene on copper particles as an additive in paraffin base oil

This study aims to examine the impact of carbon precursor materials, which are oil palm fiber (OPF) and waste polystyrene (PS), on friction and wear properties of paraffin base oil added with graphene-coated copper (Cu) additive. The graphene was synthesized on Cu particles via hydrogen-free chemical vapor deposition method. The graphene was characterized using Raman spectroscopy and transmission electron microscopy. The lubricity properties of 0.6 wt.% of synthesized graphene-coated Cu additive in paraffin base oil was analyzed based on its tribological behavior using a four-ball tribometer. From the quantitative and qualitative characterization analysis, graphene-coated Cu additive synthesized using 50 wt.% OPF carbon precursors has a good-quality graphene with minimal defects and a well-ordered lattice structure. From the tribological analysis, the paraffin base oil added with graphene-coated Cu additive synthesized using 50 wt.% OPF carbon precursor has the lowest coefficient of friction of 0.07 and wear rate of 1.6 × 10−5 mm3/min. Hence, it can be suggested that incorporating graphene-coated Cu particles, synthesized from a 50 wt.% OPF carbon precursor, into base oil shows great potential as an environmentally friendly additive, particularly in terms of enhancing lubrication performance.