The stabilities and electronic structures of single-layer bismuth oxyhalides for photocatalytic water splitting

Abstract

The stabilities and electronic/band structures of single-layer bismuth oxyhalides have been investigated by employing first-principles calculations. The results indicate that the single-layer bismuth oxyhalide materials, except for BiOF, have robust energetic and dynamical stabilities because of their low formation energies and the absence of imaginary frequencies within the entire Brillouin zone. Furthermore, calculations of the electronic structures and optical absorptions indicate that single-layer BiOI possesses a favorable band gap, suitable band edge positions, different orbital characteristics and different effective masses at the valence band maximum (VBM) and conduction band minimum (CBM), thus presenting excellent photocatalytic activity for water splitting. Moreover, the resulting compressive strains can shift the band edge positions of the single-layer materials to more suitable places to enhance their photocatalytic activities.

MnPSe3 Monolayer: A Promising 2D Visible‐Light Photohydrolytic Catalyst with High Carrier Mobility

“…Moreover, 2D nature means short distance for the generated electrons and holes to migrate, reducing the possibility of electron–hole recombination, and then giving high quantum yields. Enlightened by some 2D materials which are predicted to be photocatalysts for water splitting under visible light,[[qv: 15b]],16 and especially some proved good photocatalysts in experiments such as g‐C 3 N 4 ,17 we investigated the band edges and optical properties of MPS 3 (M = Fe, Mn, Ni, Cd, Zn) and MPSe 3 (M = Fe, Mn) monolayers to screen more proper photocatalysts for water splitting. Then the carrier mobility was calculated through deformation potential (DP) theory for MnPSe 3 monolayer which is a direct‐band‐gap semiconductor and has strong absorption in the visible‐light region.…”

Indirect-Direct Band Transformation of Few-Layer BiOCl under Biaxial Strain

“…12 It has also been demonstrated by first-principle methods that the monolayer BiOX (except BiOF)with better photocatalytic activitiesare stable and the applied strains can improvetheir H2 production by tuning the position of CBM. 13 Although experimental and theoretical explorations about BiOX have been extensively done,most of the reports focused on the photocatalytic properties. [14][15][16] In-depth studies on other aspects are still lacking, such as electronic structure designs of BiOX with a few layers.…”

Mechanochemically prepared BiOCl nanoplates for removal of rhodamine B and pentachlorophenol

“…Morphology of the nanomaterials have a great effect on their properties and applications [61]. The indirect band gap nature of BiOX would also help to prohibit the electron-hole recombination [62]. Consequently, the factors such as more separated nanoplates and therefore abundant available active A.…”