Mechanical and Interface Properties of Carbyne Chains on Metallic Surfaces

Carbyne, the smallest nanofiber, is of great interest due to its high modulus and stiffness compared to other carbon allotropes such as graphene or carbon nanotubes. However, it is difficult to synthesize and maintain the structure of carbyne without the presence of a substrate. In this study, we will discuss the mechanics of carbyne on metallic surfaces and predict its mechanical and interface properties for application in a nanocomposite. Metal based nanocomposites that need to achieve high mechanical strength require a high elastic modulus material as the fiber in the nanocomposite. Low dimensional materials such as carbyne with a high elastic modulus are ideal candidates for such application, however, the interface properties between carbyne with metals becomes a critical factor in achieving the desired strength. We use molecular dynamics to find the stiffness and stress distributions under bending for carbyne with different end caps, and carbyne encapsulated in carbon nanotubes on a Ni (1 1 1) surface. <i>Ab initio</i> calculations are then performed to predict the interface bonding properties as the nickel-carbyne interface undergoes bending. We predict carbyne’s bending stiffness and determine the reason for why the mechanical strength is not fully utilized while placing the carbyne on a nickel surface.