Fully auxetic and multifunctional of two-dimensional δ -GeS and δ -GeSe

Designing and Development of AsP–GeY (S; Se) In-Plane and van der Waals Heterojunction-Based Photonic Devices for Wavelength Tuning

“…37,38 The physical properties of group IV monosulfide compounds are closely linked to the types of sulfur atoms (S, Se, or Te). 39 For instance, Ge and Sn monosulfide compounds containing S and Se exhibit the characteristics of large bandgap semiconductors, while those containing Te possess smaller bandgaps and exhibit higher doping concentrations. 40,41 As analogs of BP, Eli Sutter et al reported the successful fabrication of a large (up to 20 μm) ultrathin sheets of GeY (Y = Se; S) using a vapor transport process.…”

“…Following graphene, black phosphorus (BP) has gained widespread use in developing various functional devices due to its excellent physical and chemical properties. , However, the instability of BP in ambient air severely limits its potential as a nanoelectronics device. − Recently, as a derivative of BP, black arsenic phosphorus (AsP)a binary alloyhas been successfully fabricated, offering superior stability and showing promise as an infrared photoelectric detector material. − AsP, a member of the black AsP family, exhibits remarkable merits such as extremely high carrier mobility (electron mobility of 10,000 cm 2 V –1 s –1 ) and tunable electronic structure. , Nonetheless, the absorption wavelength corresponding to the medium band gap of AsP restricts its application range . Group IV monothiophiles (MX, M = Ge, Sn; X = S, Se, Te) are a class of materials that have recently attracted considerable attention in research and various applications , due to their intriguing electronic, thermoelectric, and ferroelectric properties, as well as their unique bonding mechanisms. , The physical properties of group IV monosulfide compounds are closely linked to the types of sulfur atoms (S, Se, or Te) . For instance, Ge and Sn monosulfide compounds containing S and Se exhibit the characteristics of large bandgap semiconductors, while those containing Te possess smaller bandgaps and exhibit higher doping concentrations. , As analogs of BP, Eli Sutter et al reported the successful fabrication of a large (up to 20 μm) ultrathin sheets of GeY (Y = Se; S) using a vapor transport process.…”

Predicting Novel 2D AsBiX3 (X = S, Se, and Te) Auxetic Monolayers with Favorable Optical and Photocatalytic Water-Splitting Properties

“…Moreover, it has been found that NPR is present in a large number of 2D materials and can occur in-plane, out-of-plane, or in both orientations. As an example of, (i) 2D with in-plane NPR: penta-graphene, Be 5 C 2 , B 2 N 4 , W 2 C, penta-C 2 , B 2 Al, 1T-MX 2 (M = Mo, W, Tc, and Re; X = S, Se, and Te), and MB 2 (M = Be, Mg, Fe, Ti, Hf, V, Nb, and Ta); ,− (ii) 2D with out-of-plane NPR: borophene, SnSe, TiN, and BP 5 ; ,, and (iii) 2D with both in-plane and out-of-plane NPRs: GaPS 4 , Ag 2 S, δ-GeS, and δ-GeSe. ,, These materials possess reentrant or hinged geometric structures, which are thought to be the main cause of auxetic behavior. In addition, the auxetic effects can provide a range of material performance improvements, including fracture toughness, enhanced indentation resistance, and energy absorption .…”

Atomic and electronic structure of monolayer ferroelectric GeS on Cu(111)

“…使用的Cu(111)衬底首先通过多次溅射和 退火循环处理, 直到LEED图案中观察到尖锐的 文献中报道的同族单层SnS和SnSe薄膜 [27,29] . 目 前理论计算预测第Ⅳ主族单硫属化合物具有多种 同素异形体, 分别是 , , , 和 相 [27,[38][39][40][41][42][43] , 但 目前实验上已报道的为 相和 相. 除 相外, 其 他结构相都是boat或六边形原子结构排列 [44] , 因 (208 cm -1 ), (248 cm -1 )和 (282 cm -1 ), 与文 献报道结果基本一致 [48] , 说明我们所制备的薄膜 是高质量单层GeS薄膜(补充材料图S2 (online)).…”