This study investigates the effect of exchange-correlation on the electronic properties of hybridized hetero-structured nanomaterials, called single-walled carbon boron nitride nanotubes (SWCBNNT). A first principles (ab initio) method implemented in Quantum ESPRESSO codes, together with different parametrizations (local density approximation (LDA) formulated by Perdew Zunga (PZ) and the generalized gradient approximation (GGA) proposed by Perdew–Burke–Ernzerhof (PBE) and Perdew–Wang 91 (PW91)), were used in this study. It has been observed that the disappearance of interface states in the band gap was due to the discontinuity of the π–π bonds in some segments of SWCNT, which resulted in the asymmetric distribution in the two segments. This work has successfully created a band gap in SWCBNNT, where the PBE exchange-correlation functional provides a well-agreed band gap value of 1.8713 eV. Effects of orbitals on electronic properties have also been studied elaborately. It has been identified that the Py orbital gives the largest contribution to the electrical properties of our new hybrid SWCBNNT nanostructures. This study may open a new avenue for tailoring bandgap in the hybrid heterostructured nanomaterials towards practical applications with next-generation optoelectronic devices, especially in LED nanoscience and nanotechnology.

Carbon Nanotubes: A Review of Synthesis and CharacterizationMethods/Techniques IntroductionWith the discovery of lower dimensional forms of carbon with unique mechanical properties in many areas of technology especially in nanotechnology (Popov V. , 2004), over the years until recent, the discovery was not made about nanostructure, particles and fibers and their applications are also not known. In 1991 carbon nanotubes were discovered by Iijima (Resel Das, Sharifah Bee Abd Hamid, 2015) and they have received much attention because of their usefulness in mechanical (

Due to greater demand to use 1D semiconducting chips to replace semiconductors made from bulk structures We studied the structural and electronic properties of free (7, 0) metallic oxides and non-metallic carbide nanotubes. SWMgONT, SWZnONT and SWSiCNT were chosen as the representative model. All the quantum simulation studies were done within DFT ab’initio implemented in quantum ESPRESSO. Results obtained for structural properties revealed that the most stable bond lengths of MgONT, ZnONT and SiCNT are 1.80 Å, 1.82 Å and 1.42 Å respectively. The results obtained revealed 2.8 eV band gap for SWMgONT, 0.5 eV for SWZnONT and 0.8 eV for SWSiCNT respectively. Furthermore SWMgONT and SWZnONT are regarded as direct band gap semiconductors while SWSiCNT is regarded as an indirect semiconductor with narrow band gap. The narrow band gap of all the three systems obtained demonstrates their potential in the optoelectronic application in the next generations’ sustainability science and technology. Recent studies showed that explorations were conducted on oxide nanotubes such SiO2NT, however to the best of our knowledge, studies of the oxide nanotubes of Mg, Zn and Si have not been reported, hence few literature are available.

Initially, three samples of carbon nanotubes (SWCNTs) were synthesized from neem tree material. Afterward, these samples were coated with hexagonal boron nitride (h-BN) to form h-BN and CNT composite (h-BN-CNT). The essence of using h-BN (being a perfect insulator) with armchair SWCNT (being a conductor) is to create an interface between an insulator and conductor. The samples were treated under three different transition metal nanoparticles; silver, iron, and nickel. Thermogravimetric (TGA) analysis reveals that h-BN/CNT is thermally more stable with silver than iron and nickel nanoparticles. TGA profile showed resistance to mass loss at the beginning due to the higher thermal resistivity by the impurity compounds. The DFT calculation, generalized gradient approximation (GGA), and Perdew–Burke–Ernzerhof (PBE) analysis found engineered bandgap energy of 3.4 eV for the synthesized h-BN-CNT heterostructure. Because of its unique structural and electronic properties such as tunable bandgaps, the h-BN-CNT heterostructure may open new ways for manipulating excitons in the CNTs, and thus can be explored to develop various new electronic devices.

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