UV resistance and tribological properties of β-diketone organic molybdenum as lubricating additive in aluminum complex grease

Purpose This study aims to extend the service life and applicability under ultraviolet (UV) irradiation conditions, the authors reveal the strong UV resistance of dibenzoylmethane molybdenum (MDBM) in aluminum-based greases by analyzing the effect of UV radiation on the rheological properties, antioxidant properties and UV absorption. Meanwhile, the authors evaluate the tribological properties of MDBM under different sliding modes and applied loads in aluminum-based greases. Design/methodology/approach In this work, the authors designed and synthesized an S- and P-free MDBM through a simple one-pot method and examined the tribological and UV-resistant performance of MDBM within aluminum complex grease. Findings The results show that MDBM has good friction-reducing and anti-wear properties, which is attributed to the adsorption of the MDBM itself and the generation of minor amount of MoO3 on the worn surface at a maximum Hertzian contact pressure of 0.6 Gpa. The authors also reveal the strong UV resistance of MDBM in aluminum-based greases by analyzing the effect of UV radiation on the rheological properties, antioxidant properties and UV absorption, which is mainly attributed to self-keto-enol isomer interconversion from the special structure of β-diketone. Originality/value The work demonstrates a feasible way to develop novel multifunctional UV resistance organic molybdenum lubricating materials. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2025-0048/