Chemical and Bandgap Engineering in Monolayer Hexagonal Boron Nitride

Abstract

Monolayer hexagonal boron nitride (h-BN) possesses a wide bandgap of ~6 eV. Trimming down the bandgap is technically attractive, yet poses remarkable challenges in chemistry. One strategy is to topological reform the h-BN’s hexagonal structure, which involves defects or grain boundaries (GBs) engineering in the basal plane. The other way is to invite foreign atoms, such as carbon, to forge bizarre hybrid structures like hetero-junctions or semiconducting h-BNC materials. Here we successfully developed a general chemical method to synthesize these different h-BN derivatives, showcasing how the chemical structure can be manipulated with or without a graphene precursor, and the bandgap be tuned to ~2 eV, only one third of the pristine one’s.

Density Functional Theory Study of Aspirin Adsorption on BCN Sheets and their Hydrogen Evolution Reaction Activity: a Comparative Study with Graphene and Hexagonal Boron Nitride

“…Our results are consistent with the theoretical results where h‐BN was found to have band gap of 4.47 eV . Experimentally measured band gap of h‐BN is 6.07 eV . The reason that the calculated band gap is less than the experimental value is due the fact that DFT always underestimates the band gap.…”

Band Gap Engineering of Hybrid 2-D Nanomaterials Some Recent Developments

“…In the alternative option, it was substituting C atoms to form hybrid lattice of h-BNC in place of h-BN. A general chemical method reported in this context to prepare different h-BN derivatives confirmed that the chemical structure could very well be modified with or without a graphene precursor to tune the BG up to ~2eV [23][24][25].…”

“…It is quite likely that hybrid structure are constituted with alloys or mixed domains of h-BN, graphene and h-BNC. Especially, when the conversion exceeds 15min, the D peak of graphene starts to slowly blue shift from 1354 cm −1 to the h-BN's E2g peak at 1368 cm −1 [23,26,30,31].…”

“…Alternately, introducing foreign atoms like C forges hybrid structures like hetero-junctions or semiconducting h-BNC materials. A general chemical method of synthesizing these different versions of h-BN derivatives was showcased for manipulating the chemical structure either with or without a graphene precursor, resulting in BG down to ~2 eV [71].…”

“…In recent experiments, co-deposition of graphene and h-BN was attempted to form hybridized h-BNC besides synthesizing atomic layers of h-BNC by substituting C atoms in graphene layer with B and N atoms. The significance of the chemical and electrical tunability achieved in these experimental methods motivated using PECVD to synthesize several other members of h-BN derivatives [23,[26][27][28][29].…”