Interfacial defect engineering and photocatalysis properties of hBN/MX ₂ (M = Mo, W, and X = S, Se) heterostructures

Abstract

Van der Waals (VDW) heterostructures have attracted significant research interest due to their tunable interfacial properties and potential in a wide range of applications such as electronics, optoelectronic, and heterocatalysis. In this work, the impact of interfacial defects on the electronic structures and photocatalytic properties of hBN/MX2(M = Mo, W, and X = S, Se) are studied using density functional theory calculations. The results reveal that the band alignment of hBN/MX2 can be adjusted by introducing vacancies and atomic doping. The type-I band alignment of the host structure was maintained in the heterostructure with n-type doping in the hBN sublayer. Interestingly, the band alignment changed to the type-II heterostructrue as VB defect and p-type doping was introduced in the hBN sublayer. This could be profitable for the separation of photo-generated electron−hole pairs at the interfaces and is highly desired for heterostructure photocatalysis. In addition, two Z-type heterostructures including hBN(BeB)/MoS2, hBN(BeB)/MoSe2, and hBN(VN)/MoSe2 were achieved, showing reducing band gap and ideal redox potential for water splitting. Our results reveal the possibility of engineering the interfacial and photocatalysis properties of hBN/MX2 heterostructures via interfacial defects.

Clean Production of Hydrogen Peroxide: A Heterogeneous Solar‐Driven Redox Process

“…Given the similar chemical characteristics of O and S, increasing efforts have been devoted to investigating SVs for metal chalcogenides. [ 154 ] Recently, novel zirconium trisulfide (ZrS 3 ) nanobelts with disulfide (S 2 2− ) and sulfide anion (S 2− ) vacancies were also proposed for PC ORR and the simultaneous oxidation of benzylamine to benzonitrile. [ 71 ] ZrS 3 with only S 2 2− vacancies was denominated as ZrSS 2− x , and the one with both S 2 2− and S 2− vacancies was named ZrS 1− y S 2− x .…”

Insights into Tuning of Mo‐Based Structures toward Enhanced Electrocatalytic Performance of Nitrogen‐to‐Ammonia Conversion

“…[ 19 ] The corresponding DFT study suggested that the Mo sites at edges of MoS 2 were the adsorption sites for N 2 as the sites were undercoordinated and initiated NRR. Accordingly, to achieve more such Mo catalytic sites, MoS 2 nanosheets were modified through synthesis of ultrathin nanosheets [ 20 ] or morphological tuning into nanoflowers [ 21 ] . In the latter case, the barrier toward formation of *N 2 H 2 intermediates was decreased, which is the rate‐determining step (RDS) of NRR, on the Mo sites.…”

2-inch semi-polar (112̄2) AlN templates prepared by high-temperature hydride vapor phase epitaxy

“…11 Compared to polar (0002) AlN, the growth of high-quality single-phase semi-polar (112̄2) AlN is more difficult because of the anisotropic migration of adsorbed atoms on the growth surface. 12 Moreover, various crystal orientations such as (112̄2), (101̄3), and (101̄1) AlN are all possible to appear on m -plane sapphire substrates, resulting in polycrystalline AlN. 13,14 Researchers have achieved single-crystal (112̄2) AlN using metal–organic chemical vapor deposition (MOCVD) with pre-treatments such as sapphire nitridation and buffer layer introduced prior to AlN deposition.…”