Lattice-Matched Epitaxial Graphene Grown on Boron Nitride

Abstract

Lattice-matched graphene on hexagonal boron nitride is expected to lead to the formation of a band gap but requires the formation of highly strained material and has not hitherto been realized. We demonstrate that aligned, lattice-matched graphene can be grown by molecular beam epitaxy using substrate temperatures in the range 1600-1710 °C and coexists with a topologically modified moiré pattern with regions of strained graphene which have giant moiré periods up to ∼80 nm. Raman spectra reveal narrow red-shifted peaks due to isotropic strain, while the giant moiré patterns result in complex splitting of Raman peaks due to strain variations across the moiré unit cell. The lattice-matched graphene has a lower conductance than both the Frenkel-Kontorova-type domain walls and also the topological defects where they terminate. We relate these results to theoretical models of band gap formation in graphene/boron nitride heterostructures.

Anomalous Low Thermal Conductivity of Atomically Thin InSe Probed by Scanning Thermal Microscopy

“…[ 75 ] However, our SThM of InSe on hBN did not reveal any significant increase in thermal conductance compared to InSe on SiO 2 (Figure S4, Supporting Information). This unexpected result could potentially originate from strain caused by lattice mismatch (ε = [ a InSe – a hBN ]/ a InSe ≈ 37%), [ 76,77 ] thermal expansion mismatch and/or rotational crystal misalignment. These factors can affect the thermal resistance at the interface of 2D vdW crystals.…”

Moiré-Modulated Conductance of Hexagonal Boron Nitride Tunnel Barriers

“…This indicates that the hBN lattice is compressively strained by ∼0.24% in this region, assuming that the hBN and graphite lattices are perfectly aligned. 13 , 14 , 37 − 39 …”

Metal‐free graphene/boron nitride heterointerface for CO2 reduction: Surface curvature controls catalytic activity and selectivity

“…Figure presents the optimized structures of G‐BN armchair nanoribbons and nanotubes. G‐BN heterostructures can be regarded as the combination of zigzag graphene and zigzag BN, which have the similar crystal structures and lattice constants (only 1.8% mismatch) . After the combination of graphene and BN, G‐BN nanomaterials exhibit some unique characteristics, such as band gap opening, excellent thermal transport, and intrinsic half‐metallic behavior .…”

“…G-BN heterostructures can be regarded as the combination of zigzag graphene and zigzag BN, which have the similar crystal structures and lattice constants (only 1.8% mismatch). 28,29 After the combination of graphene and BN, G-BN nanomaterials exhibit some unique characteristics, such as band gap opening, excellent thermal transport, and intrinsic halfmetallic behavior. 16,30 For the G-BN armchair nanotubes, previous works have proved that the smallest nanotube which can be constructed is G-BN (3).…”