Partially Oxidized Violet Phosphorus as an Excellent Lubricant Additive for Tribological Applications

As a novel two-dimensional material, violet phosphorus(VP) hasattracted a considerable amount of attention due to its high carriermobility, anisotropy, wide band gap, stability, and easy strippingproperties. In this work, the microtribological properties of partiallyoxidized VP (oVP) and the mechanism of reducing friction and wearas additives in oleic acid (OA) oil were studied systematically. Whenadding oVP to OA, the coefficient of friction (COF) decreased from0.084 to 0.014 with the steel-to-steel pair, and the ultralow shearingstrength tribofilm consisting of amorphous carbon and phosphorus oxidesthat formed resulted in the reductions of COF and wear rate individuallyby 83.3% and 53.9%, respectively, compared with those of pure OA.The results extended the application scenarios for VP in the designof lubricant additives.