Graphitic Biocarbon from Agrowaste Biomass: A Sustainable Material of Excellent Lubrication Performance

Sustainable and ecofriendly materials are gaining immense interest in various engineering applications to minimize environmental footprints. In particular, biomass-derived carbon materials with controlled structural features play important roles in the development of structural and functional composites for different industrial applications. The biomass-based lamellar structured carbon materials hold significant potential for tribological applications. The present work demonstrates the synthesis of graphitic domains-enriched biocarbon from lignocellulosic agrowaste biomass and its application as a sustainable material of excellent lubrication performance. The structural, chemical, and morphological properties of biocarbons were probed by Raman, infrared, X-ray photoelectron spectroscopy, and transmission electron microscopy measurements. Octadecyltrichlorosilane was grafted on the biocarbon surface to make it compatible with mineral lube base oil for long-term dispersibility. The tribological experiments were conducted by ASTM D4172-B and ASTM D5183-21a test methods. The stable dispersion of biocarbon in mineral lube base oil extended excellent lubrication performance by reducing the friction coefficient (36%) and wear volume (64%) of the steel tribopair. The Raman results signified graphitic biocarbon-based thin film deposition on tribo surfaces, which protected the contact interfaces to minimize wear and decreased the friction coefficient. The excellent dispersibility, low resistance-to-shear by lamellar pattern, the excellent affinity of biocarbon to the steel surface, and the formation of graphitic biocarbon-based tribo thin films collectively improved the lubrication performance.