STRUCTURAL, ELECTRONIC, AND ELECTRON TRANSPORT PROPERTIES OF CHEMICALLY MODIFIED PENTAGONAL SiC₂ NANORIBBONS

Two-dimensional monolayer pentagonal silicon dicarbide (_pSiC₂) and its one-dimensional nanoribbon derivative (_pSiC₂NR) possess novel electronic properties, possibly leading to many potential applications. In this chapter, we have systematically investigated the structural, electronic, and transport properties of _pSiC₂NRs using chemical function and strain engineering. The energy gaps of the _pSiC₂NRs (ZZ-ribbon, ZA-ribbon, AA-ribbon, and SS-ribbon) are created mainly owing to the competition in the edge structures, finite-size confinements, and asymmetry of chemical bonds in the tetrahedral lattice or chemical modification. By applying uniaxial tensile or compressive strain, it is possible to modulate the physical properties of _pSiC₂NRs, which subsequently change the transport behavior of the carriers. Interestingly, the pentagon network of SS-_pSiC₂NRs is still maintained, but the bond length along the strained direction undergoes a large change. The electronic band structure and bandgap are strongly affected by the uniaxial compressive strain. The evolution of bandgap versus strain is linear. The I-V characteristic of SS-_pSiC₂NR seems to be more sensitive to compressive strain than stretch strain. The ultrahigh and strainmodulated carrier mobility in monolayer penta-SiC₂ may lead to many novel applications in high-performance electronic devices. Furthermore, the unusual properties of the _pSiC₂ nanoribbons render them with great potential for applications in optoelectronic devices, especially in photovoltaics.