First-principles insight into the interfacial properties of epitaxial Bi2O2X (X = S, Se, Te) on SrTiO3 substrates

Effect of Hydrostatic Pressure on Lone Pair Activity and Phonon Transport in Bi2O2S

“…Recently, dibismuth dioxychalcogenides, Bi 2 O 2 Ch (Ch = S, Se, Te), and their 2D counterparts − have garnered tremendous research interest due to their potential applications in thermoelectrics, ,, ferroelectrics, and optoelectronics. ,,− Bi 2 O 2 (Se/Te) crystallizes in the body-centered tetragonal (SG: I 4/ mmm , Z = 1 formula units (fu) per primitive cell) anti-ThCr 2 Si 2 -type structure, while Bi 2 O 2 S prefers to crystallize in the low-symmetry primitive orthorhombic structure (SG: Pnmn , Z = 2 fu) per primitive cell) due to the stereochemically active 6s 2 lone pair of Bi 3+ cations. The stereochemically active lone pair creates a structural distortion, causing a material to crystallize in relatively low symmetry compared to materials with stereochemically inactive lone pairs. , The crystal structure of Bi 2 O 2 Ch consists of alternating Bi 2 O 2 and chalcogen (S/Se/Te) layers, which are held together by strong electrostatic forces , in contrast to van der Waals (vdW) interactions that are typically observed in layered materials. − Infrared, Raman spectra, and strain effects on bulk and monolayer Bi 2 O 2 Ch crystals have been systematically investigated to explore their possible applications in nanoelectronics …”

Bi2O2Te Nanosheets Saturable Absorber‐Based Passive Mode‐Locked Fiber Laser: From Soliton Molecules to Harmonic Soliton

“…2D bismuth oxychalcogenides (Bi 2 O 2 X: X = S, Se, Te) are a novel class of highly anisotropic zipper layered ternary compound semiconductor materials that have attracted extensive attention in nanoelectronics and nano-photonics due to their unique crystallographic structure, extraordinary electrical properties, superior ferroelectric/ferroelasticity, potential photocatalytic activity, outstanding photo response, and excellent ambient stability. [1][2][3][4][5] In contrast to traditional 2D materials (i.e., graphene, [6] black phosphorus (BP), [7] topological insulators (TIs), [8] bismuthene, [9] etc. ), in which the layer-layer is held by Van der Waals forces, Bi 2 O 2 X is a revolutionary 2D material, in which the strong covalently bonded [Bi 2 O 2 ]n 2n+ layers are sandwiched by planar X (S, Se, Te)n 2n− layers with relatively weak electrostatic interaction forces.…”

High Mobility and Quantum Oscillations in Semiconducting Bi2O2Te Nanosheets Grown by Chemical Vapor Deposition

“…Subsequently, we tried to synthesize the ultrathin films of layered Bi 2 O 2 Te by a CVD method on mica substrate, whose atomically flat surface and non-neutral layered feature are beneficial to lower the surface potential of 2D Bi 2 O 2 Te during CVD growth. As pointed out by the previous theoretical calculations, 26,31 the formation of stable Bi 2 O 2 Te is quite challenging for its narrow window of chemical potential and the existence of vairous binary phases. Here, two simple substances of Te and Bi 2 O 3 were chosen as evaporation sources (Figure 1c), which were separatedly located at two To verify the crystal structure and chemical compositions of as-synthesized 2D Bi 2 O 2 Te crystals, transmission electron microscope (TEM) imaging along two zone axes (namely [001] and [010]) were conducted.…”

“…The aforementioned Bi 2 O 2 Se series’ works have led to increasing research interest in the investigation of the whole 2D Bi 2 O 2 X family, which possesses intriguing non-neutral crystal structures composed of alternatively stacked [Bi 2 O 2 ] n 2 n + layers and [X] n 2 n – layers, small electron effective mass, and tunable band gaps. − Compared to Bi 2 O 2 Se, Bi 2 O 2 Te was predicted to have smaller effective mass, larger spin–orbit coupling, and ferroelectricity under in-plane stress, suggesting the possible rich physics and more excellent electrical properties. , However, few studies of Bi 2 O 2 Te have been done so far, − probably attributed to its lack of efficient ways to achieve the growth of ultrathin Bi 2 O 2 Te films. Recent theoretical work on thermodynamics of growth in Bi 2 O 2 X family clearly pointed out that it is most difficult to synthesize stable Bi 2 O 2 Te because of the existence of various binary phases and the narrow window of chemical potential .…”