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Studies have shown that hybrid powder materials based on natural layered silicates developed by the chemists of the Far Eastern Federal University (FEFU) and the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS) decrease the friction ratio in metals sevenfold. These new materials offer new prospects for the development of more efficient anti-friction additives, increasing the durability of spare parts for equipment and vehicles.

The work was carried out by research associates of the School of Natural Sciences and Engineering School of FEFU, as well as the Institute of Chemistry of FEB RAS. The research running led by Nikolay Shapkin, professor of the Department of General, Inorganic, and Organoelement chemistry at FEFU. The results were published in Inorganic Materials.

The scientists report two hybrid composite materials based on natural layered silicates and plant products. The first was obtained from nontronite silicate isolated from Popov Island in the vicinity of Vladivostok and modified with alkaline rice husk hydrolysate. Experiments have shown that applying this powder reduces the deterioration of friction-producing parts 2.5 to seven times. Another material based on vermiculite from Karelia and modified with regular cellulose reduced the friction ratio 1.6 times.

Scientists at the U.S. Department of Energy’s Argonne National Laboratory have found a way to use tiny diamonds and graphene to give friction the slip, creating a new material combination that demonstrates the rare phenomenon of “superlubricity.”

Led by nanoscientist Ani Sumant of Argonne’s Center for Nanoscale Materials (CNM) and Argonne Distinguished Fellow Ali Erdemir of Argonne’s Energy Systems Division, the five-person Argonne team combined diamond nanoparticles, small patches of graphene – a two-dimensional single-sheet form of pure carbon – and a diamond-like carbon material to create superlubricity, a highly-desirable property in which friction drops to near zero.

According to Erdemir, as the graphene patches and diamond particles rub up against a large diamond-like carbon surface, the graphene rolls itself around the diamond particle, creating something that looks like a ball bearing on the nanoscopic level. “The interaction between the graphene and the diamond-like carbon is essential for creating the ‘superlubricity’ effect,” he said. “The two materials depend on each other.”