Epitaxial hexagonal boron nitride on Ir(111): A work function template

Abstract

Hexagonal boron nitride (h-BN) is a prominent member in the growing family of two-dimensional materials with potential applications ranging from being an atomically smooth support for other 2D materials to templating growth of molecular layers. We have studied the structure of monolayer h-BN grown by chemical vapour deposition on Ir(111) by low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) experiments and state-of-the-art density functional theory (DFT) calculations. The lattice-mismatch between the h-BN and Ir(111) surface results in the formation of a moiré superstructure with a periodicity of $\sim$29 Å and a corrugation of $\sim$0.4 Å. By measuring the field emission resonances above the h-BN layer, we find a modulation of the work function within the moiré unit cell of $\sim$0.5 eV. DFT simulations for a 13-on-12 h-BN/Ir(111) unit cell confirm our experimental findings and allow us to relate the change in the work function to the subtle changes in the interaction between boron and nitrogen atoms and the underlying substrate atoms within the moiré unit cell. Hexagonal boron nitride on Ir(111) combines weak topographic corrugation with a strong work function modulation over the moiré unit cell. This makes h-BN/Ir(111) a potential substrate for electronically modulated thin film and hetero-sandwich structures.

8 pages, 5 figures

References in corpus (6)

• Boron nitride substrates for high-quality graphene electronics
• Massive Dirac fermions and Hofstadter butterfly in a van der Waals heterostructure
• Topological surface state under graphene for two-dimensional spintronics in air
• Formation of dispersive hybrid bands at an organic-metal interface
• The Structure and Local Variations of the Graphene Moiré on Ir(111)
• Local deformations and incommensurability of high quality epitaxial graphene on a weakly interacting transition metal

Cited by in corpus (19)

• Molecular Assembly on Two-Dimensional Materials
• Band gap renormalization and work function tuning in MoSe2/hBN/Ru(0001) heterostructures
• Epitaxial Growth of Two-dimensional Insulator Monolayer Honeycomb BeO
• Van der Waals epitaxy of two-dimensional single-layer h-BN on graphite by molecular beam epitaxy: Electronic properties and band structure
• Nanoscale probing of image-potential states and electron transfer doping in borophene polymorphs
• Microanalysis of single-layer hexagonal boron nitride islands on Ir(111)
• Large potential steps at weakly interacting metal-insulator interfaces
• Electronic Characterization of a Charge-Transfer Complex Monolayer on Graphene
• Benchmarking van der Waals-treated DFT: The case of hexagonal boron nitride and graphene on Ir(111)
• Single- and many-particle description of scanning tunneling spectroscopy
• Large effect of the metal substrate on the magnetic anisotropy of Co on hexagonal Boron Nitride
• Quantum Trapping on MoS2 through Lifetimes of Resonant Electrons: Revealing Pauli Exclusion Principle
• Fermi Level Modulation of Boron Nitride Nanosheets by Vacancy Driven Compressive Strain
• Superlubricity of Borophene: Tribological Properties in Comparison to hBN
• Atomic-resolution structural and spectroscopic evidence for the synthetic realization of two-dimensional copper boride
• Unidirectional Nano-Modulated Binding and Electron Scattering in Epitaxial Borophene
• Growth of aligned and twisted hexagonal boron nitride on Ir(110)
• Nanoscale electronic transparency of wafer-scale hexagonal boron nitride
• Epitaxial two-dimensional membranes under intrinsic and extrinsic strains