Growth of MoS₂ Nanotubes Templated by Halloysite Nanotubes for the Reduction of Friction in Oil

Abstract

One-dimensional MoS 2 nanotubes with the specific surface area of 89.34 m 2 /g and the average pore size of 2.52 nm were successfully synthesized by the thermolytical approach assisted by halloysite nanotubes. The tribological properties of MoS 2 nanotubes with good dispersion in oil were tested with a four-ball wear tester. The tribological testing results indicated that the average friction coefficient and the average wear scar diameter of the 0.08 wt % MoS 2 -based oil at 25 °C decreased about 39.2 and 35.0%, respectively, compared to those of the 150 SN base oil, indicating that the as-prepared MoS 2 nanotubes as a lubricating additive can enhance the tribological performances. Finally, the lubrication mechanism of MoS 2 nanotubes was put forward.

A review of recent advances in tribology

“…Chemically-modified GO in hydrophobic ionic liquids [132], 4-n-pentyl-4'-cyanobiphyl liquid crystal (5CB) added with graphene [128], graphene sheets anchored with molybdenum disulfide (MoS 2 ) nanoflowers [133], ILs with graphene [134,135], chemicallybonded phosphorus-graphene hybrid [136], alkyl phosphate modified graphene oxide [137], and polyhedral oligomeric silsesquioxane (POSS) grafted graphene oxide [138], were synthesized and used as liquid lubricants or additives. The research on transition metal disulfides (TMDs) liquid additives, especially MoS 2 , mainly focused on the preparation of functional MoS 2 nanosheets [118,139], MoS 2 nanotubes [140,141], hollow fullerene-like MoS 2 [142], Fe 3 O 4 @MoS 2 core-shell nanocomposites [143], and MoS 2 /montmorillonite nanocomposites [144], etc. A new 2D-layered material, black phosphorus (BP), has been used as liquid lubricant additives recently [119].…”

Hydrothermal-assisted shearing exfoliation for few-layered MoS2 nanosheets

“…The friction reducing mechanism suggests that the MoS 2 nanosheets in oil can smoothly slide onto the touching surface to avoid the wear of the tested steel ball. 38,39…”

Ultrasound-Assisted Alkaline Solution Reflux for As-Exfoliated MoS2 Nanosheets

“…The friction value decreasing mechanism is deduced that MoS 2 nanosheets in base oil can smoothly slip into the contact surface to prevent the wear of steel ball. 32,33…”

“…The appearance of two characteristic peaks of MoS 2 on the contact surfaces examined by MoS 2 –Li + /Na + . The friction value decreasing mechanism is deduced that MoS 2 nanosheets in base oil can smoothly slip into the contact surface to prevent the wear of steel ball. , …”