Sub-10 nm stable graphene quantum dots embedded in hexagonal boron nitride

Abstract

Stable graphene quantum dots (GQDs) have been synthesized by embedding CVD grown GQDs into sub-10 nm h-BN nanopores which is milled by helium ion microscope (HIM).

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

“…In recent work on free-standing MoS 2 , another interesting phenomenon was observed, namely that by milling with a slightly stigmated beam (again, in spot mode), rhombus-shaped nanopores could be obtained with a geometry following that of the hexagonal MoS 2 lattice [ 137 ] ( Figure 6f ). By helium FIB milling sub-10 nm pores into hBN and growing graphene into the voids, stable graphene quantum dot arrays have also been produced [ 166 ]. And when milling larger pores of 250 nm diameter into a 100 nm gold film on a glass substrate, the formation of “volcano-shaped” nanopores has been observed [ 169 ].…”

“…For the fully cleaned membranes, the scan strategy had no effect on the final pore size, since the hydrocarbon effect was no longer at play. Apart from silicon nitride, helium FIB milling has also been used to create nanopores in other free-standing membranes, with minimum pore diameter records as follows: 1.3 nm diameter in a 1 nm thick carbon nanomembrane [164], 2.6 nm diameter in single-layer graphene [145], 4 nm diameter in few-layer and monolayer hBN [152,166], and 1.3 nm diameter in monolayer MoS 2 [137]. Ion conductance and DNA translocation through helium FIB-milled graphene nanopores has been reported [167], as has the fabrication of suspended graphene nanomesh structures (3-4 nm pores on a pitch of ≤10 nm, Figure 6e) that demonstrated bandgap opening by quantum confinement [136].…”

Investigating the Electrical Properties of Monolayer and Bilayer h‐BNs via Atomic Force Microscopy

“…[ 5–8 ] Moreover, the unique structure and properties have promoted their use in various applications in the field of the dry‐lubricant, deep ultraviolet emitter, and gate‐insulating materials. [ 1,9,10 ] The most promising application of the h‐BN layer is to be used as substrates such as, growth templates, [ 11,12 ] and tunneling barriers, [ 13–16 ] because of its atomic flatness and good insulation. For example, an h‐BN layer with a modified dielectric interface was realized to improve carrier transport and heat spreading of a WSe 2 field‐effect transistor.…”

Interaction of hydrated metals with chemically modified hexagonal boron nitride quantum dots: wastewater treatment and water splitting

“…Similar to graphene hBN can form nanotubes [16,17], nanoribbons [18][19][20][21] and quantum dots [22][23][24][25][26][27][28][29]. A variety of hybrid/hetero structures of hBN with graphene have been demonstrated experimentally too [30][31][32][33][34][35][36]. The structural, electronic, magnetic, and optical properties of hBN nanotubes [37][38][39][40][41][42][43][44][45][46] and nanoribbons [46][47][48][49][50][51][52] have been a subject of investigation in semiempirical and first principles studies.…”