Tuning the Electronic and Mechanical Properties of Kagome Graphene via Hydrogenation

Abstract

Surface passivation is proved to be an effective way to adjust material properties or to explore new two-dimensional (2D) materials. Herein, we proposed three hydrocarbons with high stability for the first time via hydrogenation on the Kagome graphene, namely, C6H4, C6H6-I, and C6H6-II. Unlike the Kagome graphene, which is metallic, all these 2D monolayers are wide-bandgap semiconductors (4.06–4.81 eV). Among them, C6H4 is an indirect bandgap semiconductor, but both C6H6-I and C6H6-II possess the direct bandgap feature. Considerable carrier mobilities (102 to 103 cm2 V–1 s–1) have been further confirmed in the three hydrocarbons on the basis of modified deformation potential theory. Specifically, for C6H4, the hole mobilities are as high as 104 to 105 cm2 V–1 s–1, comparable to those of graphene and black phosphorus. The intrinsic vertical electric field induced by the asymmetric crystal structures in C6H4 and C6H6-I will be beneficial to the spatial separation of electrons and holes in semiconductors, promising in the field of optoelectronics. In addition, hydrogenation has a great influence on the mechanical properties of Kagome graphene, no matter whether it is Young’s modulus, Poisson’s ratio, or ideal tensile strength. Particularly, in-plane axial negative Poisson’s ratios (−0.011/–0.018 along the a-/b-direction) were found in C6H6-I, mainly originated from the interaction of carbon pentagons and octagons. These interesting findings in our work may pave the way for the application of hydrogenated Kagome graphene in the future.

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

“…In particular, the electron carrier mobility along the y -direction for AsBiTe 3 reaches 556.96 cm 2 /(V s). This value outperforms those of some 2D semiconductors such as MoS 2 , XTeI (X = In, Ga), As 2 Te 3 , WSSe, WSe 2 , WS 2 , and RhYX (Y = I, Cl, Br, I; X = S, Se, and Te) ,,− and comparable to those of MoSSe and C 6 H 6 , but lower than those of 2D XBiSe 3 (X = As and Sb) monolayers …”

“…In particular, the electron carrier mobility along the y-direction for AsBiTe 3 reaches 556.96 cm 2 /(V s). This value outperforms those of some 2D semiconductors such as MoS 2 , XTeI (X = In, Ga), As 2 Te 3 , WSSe, WSe 2 , WS 2 , and RhYX (Y = I, Cl, Br, I; X = S, Se, and Te) 23,59,61−63 and comparable to those of MoSSe and C 6 H 6 64,65 but lower than those of 2D XBiSe 3 (X = As and Sb) monolayers. 30 According to the obtained band gap values with the hybrid functionals HSE (1.23 < E gap < 3.00 eV), the predicted semiconducting AsBiX 3 monolayers may serve as photocatalysts for water splitting.…”

Exploring the thermoelectric properties of two-dimensional organic conjugated polymers with Dirac cone-like electronic structures

“…[27][28][29] In this paper, starting from the interaction between the lattice structure and electronic properties, we explore materials with special lattice structures-the Kagome lattice, which, with its Dirac cone-like structure, has higher carrier mobility. 20,30,31 This feature makes it an ideal candidate for organic thermoelectric materials. [31][32][33][34] We studied the thermoelectric properties of six organic conjugated polymers based on heterotriangulene (HT) derivatives with various central atoms and bridging groups.…”

“…20,30,31 This feature makes it an ideal candidate for organic thermoelectric materials. [31][32][33][34] We studied the thermoelectric properties of six organic conjugated polymers based on heterotriangulene (HT) derivatives with various central atoms and bridging groups. 30,35,36 Among them, the CTPB-polymer, with boron as the central atom and carbonyl as the bridging group, exhibits excellent potential for thermoelectric applications.…”