We report the first time that metallic homostructure of aluminene (Al) and antimonene (Sb) materials are the promising materials for the electric charge storage as a nanocapacitors. In this work, we have proposed two various phases of capacitor, namely, hexagonal (H) and trigonal (T) phases. Here, we have investigated the electronic properties, visualization of molecular orbitals, van der Waals (vdW) energy between layers, and supercapacitance properties, such as dipole moment (P), charge stored (Q(s)), energy stored (E-s), and capacitance (C). It is found that the Sb bilayer has higher capacitance values than Al bilayer. Instead of that, we have also focused on the various pristine homobilayer of boron (B), carbon (C), silicon (Si), phosphorus (P), gallium (Ga), germanium (Ge), arsenic (As), and indium (In) and heterobilayers of pristine C and Al, pristine C and Sb, pristine C and Si, pristine C and Sn, pristine C and As, and pristine P and Si for H and T phases, respectively, and results are compared with Al and Sb. Our investigated energy storage, charge, and capacitance values are in better agreement with the previously reported works. The capacitance value increased accordingly to the external electric field and behave as an ideal nanocapacitor. The results suggest that Al- and Sb-homobilayer could be flexible method for building nanoscale capacitors and nanocircuits.

Recently, a two-dimensional (2D) Si2BN monolayer material made of silicon, boron and nitrogen, was theoretically predicated and has attracted interest in the scientific community. Due to its 2D planar nature with high formation energy, Si2BN monolayers can be flexible and strong like graphene and also exhibit captivating properties like those of other 2D materials. Motivated by this fascinating graphene-like monolayer of Si2BN, we have investigated its structural and electronic properties based on first-principles calculations. The electronic band structure of pure Si2BN shows metallic behaviour. We have discovered that the band gap of Si2BN monolayer can be tuned to 102 meV by applying external electric fields and mechanical strain. The band gap opening occurs at 5% strain, where the bond angles between the nearest neighbours become nearly equal. The band gap opening occurs at a small external electric field of 0.4 V angstrom(-1). More interestingly, at room temperature, the electron mobility of Si2BN is 4.73 x 10(5) cm(2) V-1 s(-1), which is much larger than that of graphene, while the hole mobility is 1.11 x 10(5) cm(2) V-1 s(-1), slightly smaller than the electron mobility. The ultrahigh carrier mobility of Si2BN may lead to many novel applications in high-performance electronic and optoelectronic devices. These theoretical results suggest that the Si2BN monolayer exhibits multiple effects that may significantly enhance the performance of Si2BN based electronic devices.