The successful synthesis of borophene beyond the monolayer limit has expanded the family of two-dimensional boron nanomaterials. While atomic-resolution topographic imaging has been previously reported, vibrational mapping has the potential to reveal deeper insight into the chemical bonding and electronic properties of bilayer borophene. Herein, inelastic electron tunneling spectroscopy (IETS) is used to resolve the low-energy vibrational and electronic properties of bilayer-α (BL-α) borophene on Ag(111) at the atomic scale. Using a carbon monoxide (CO)-functionalized scanning tunneling microscopy tip, the BL-α borophene IETS spectra reveal unique features compared to single-layer borophene and typical CO vibrations on metal surfaces. Distinct vibrational spectra are further observed for hollow and filled boron hexagons within the BL-α borophene unit cell, providing evidence for interlayer bonding between the constituent borophene layers. These experimental results are compared with density functional theory calculations to elucidate the interplay between the vibrational modes and electronic states in bilayer borophene.
Researchers are exploring a new form of borophene, a two-dimensional material made of boron atoms, that goes beyond a single layer. This new bilayer borophene has unique properties that are being studied to understand its potential applications better.
Here's a simplified summary:
These findings provide deeper insights into the chemical bonding and electronic properties of bilayer borophene, which could be useful for future technological applications.
Monolayer borophene has a high charge capacity, mechanical strength, and low diffusion barrier, but it's not stable enough for practical use