Cubine, a Quasi Two-Dimensional Copper–Bismuth Nanosheet

Abstract

We report on the discovery of a quasi two-dimensional copper–bismuth nano sheet from ab initio calculations, which we call cubine. According to our predictions, single layers of cubine can be isolated from the recently reported high-pressure CuBi bulk material at an energetic cost of merely ≈20 meV/A2, comparable to values to separate single layers of graphene from graphite. Our calculations suggest that cubine has remarkable electronic and electrochemical properties: It is a superconductor with a moderate electron–phonon coupling λ = 0.5, leading to Tc ≈ 1 K, and can be readily intercalated with lithium with a high diffusibility, rendering it a promising candidate material to boost the rate capacity of current electrodes in lithium-ion batteries.