Carrier mobility of one-dimensional vanadium selenide (V2Se9) monolayer and nanoribbon systems: DFT study

1D group V-VI-VII ternary nanowires: moderate band gaps, easy to exfoliate from bulk, and unexpected ferroelectricity

One-dimensional nanowires have emerged as compelling ideal materials due to their characteristic structure, properties, and applications in nanodevices. Herein, based on experimental vdW-chain bulk crystals, a series of one-dimensional (1D) X^VY^VIZ^VII (X = As, Sb, Bi; Y = S, Se, Te; Z = Cl, Br, I) ternary nanowires are theoretically investigated. Such exfoliated 1D nanowires possess excellent stability and moderate band gaps (1.76-3.16 eV). The calculated electron mobilities were found to reach a magnitude of 10² cm² V^-1 s^-1 and even up to 322.95 cm² V^-1 s^-1 for 1D BiSeI nanowires, which are much larger than those of the previously reported 1D materials. Furthermore, the appropriate band edge alignments and considerable optical absorption endow 1D X^VY^VIZ^VII nanowires with prospective photocatalytic properties for water splitting. Notably, AsSI and AsSeI nanowires possess a unique non-centrosymmetric structure and exhibit promising 1D ferroelectricity. Large spontaneous polarization values, P_s, of 11.31 × 10^-10 and 6.92 × 10^-10 C m^-1 are obtained for 1D AsSI and AsSeI nanowires, respectively, and such 1D ferroelectricity can be regulated by intra-chain strains. Our calculations not only broaden the family of 1D materials but also reveal their great potential applications in electronic, optoelectronic, and ferroelectric devices.

High electron mobility and wide-bandgap properties in a novel 1D PdGeS3 nanochain

As a versatile platform, one-dimensional (1D) electronic systems host plenty of excellent merits, such as high length-to-diameter ratios, flexible mechanical properties, and manageable electronic characteristics, which endow them with significant potential applications in catalysts, flexible wearable devices, and multifunctional integrated circuits. Herein, based on first-principles calculations, we propose a versatile 1D PdGeS₃ nanochain system. Our calculations show that the 1D PdGeS₃ nanochain can be synthesized simply from its bulk crystal by exfoliation methods and can stably exist at room temperature. The 1D PdGeS₃ nanochain is an indirect semiconductor with a wide bandgap of 2.86 eV, and such a bandgap can be effectively modulated by strain. Remarkably, the electron mobility of the 1D PdGeS₃ nanochain reaches as high as 1506 cm² V^-1 s^-1, which is one to two orders of magnitude larger than those of most reported 1D materials and even some 2D materials. Such high electron mobility accompanied with low hole mobility endow the 1D PdGeS₃ nanochain with the capacity of the separation of carriers. Our work shows that the 1D PdGeS₃ nanochain is a promising candidate for applications in novel multifunctional nanoelectronic devices.