Controlled Growing of Graphdiyne Film for Friction Reduction and Antiwear

Like the multilayered graphene which is the most widely used solid lubricant, graphdiyne (GDY) as a 2D material holds potential similar prospects but has been rarely researched so far. One reason is that growing a GDY film in a controllable manner on diverse material surfaces remains a great challenge. To address the issue, a catalytic pregrowth and solution polymerization method is developed to synthesize a GDY film on various substrates. It allows fine control over film structure and thickness. A macroscopic ultralow friction coefficient of 0.08 is obtained, and a relatively long life of more than 5 h under a high load of 1378 MPa is achieved. Molecular dynamics simulations together with the surface analysis demonstrate that the increased deformation degree and weakened relative motion between GDY layers contribute to the low friction. Especially, different from graphene, the friction of GDY exhibits a double increase and decrease in one period of lambda approximate to 8-9 angstrom, and it is roughly equal to the distance between two adjacent alkyne bonds in the x direction, indicating GDY's structure and lattice play an important role in reducing friction.

Automated summary

Graphdiyne (GDY) is a promising 2D material with similar potential to multilayered graphene, but it has been rarely studied due to the challenges in growing a controllable GDY film on different surfaces. Researchers have developed a catalytic pregrowth and solution polymerization method to synthesize a GDY film on various substrates with fine control over its structure and thickness. The experimental results show that GDY has an ultralow friction coefficient and a relatively long lifespan.