فهرست مطالب حسین نیکوفرد

Due to the unique physical and chemical properties of two-dimensional (2D) materials, such as linear band structure near the Fermi level, high electrical and thermal conductivity, they have opened up a wide vision in the fabrication of nanoelectronic devices, energy storage and information transmission. One of the theses materials that has recently received attention is a two-dimensional monolayer of boron atoms called borophene which has various allotropes such as α, β12, χ3, 2-pmmn and 8-pmmn. This 2D material has tilted and anisotropic Dirac cone and in addition to excellent transparency, it has excellent electron and ion conductivity. These properties along with other properties of borophene have caused diverse and potential applications of this material in gas sensors, metal ion batteries and electronic and optoelectronic devices. In this paper, we intend to review the properties of borophene and investigate the effect of factors such as impurity, light radiation, strain, dimension reduction in the form of nanoribbon, temperature, electric and magnetic fields on the properties of electron transport in this material.

In this paper, we study the properties of electronic transport in MXene Zr2CO2 nanoribbons of armchair type (AMNR). By using the tight-binding method, we obtain the band structure of this material and investigate the electron conductance with the non-equilibrium Green's function approach. It can be seen that increasing the width of the ribbon from 5-AMNR to 20-AMNR reduces the energy gap from 1.77 eV to 1.40 eV and also increases the maximum conductance from 7 e^2⁄(h )to 18 e^2⁄(h ). Increasing the width of the ribbon to 55-AMNR will eventually lead to the reduction of the energy gap to a limit value of 1.39 eV. For a nanoribbon with a certain width of 5-AMNR, we consider carbon and zirconium vacancies in three central, edge, and linear positions and show that the vacancy can reduce the energy gap up to 1.62 eV and eliminate the step mode of conductivity. Also, in the presence of vacancy, we see a decrease in the maximum conductance, and in some cases, this decrease reaches from 7 e^2⁄(h ) (in the case without vacancy) to less than 3 e^2⁄(h ). The results of this paper indicate the ability to adjust the band gap by changing the width of the ribbon and also control the conductance by applying the vacancy. These properties show the potential applications of this kind of MXene in nanoelectronic devices.

In this work, the electrochemical behaviors of some pharmaceutical sulfonamide derivatives including sulfadiazine (SDZ), sulfathiazole (STZ), sulfaquinoxaline (SQX), sulfacetamide (SAA), and sulfasalazine (SSZ) on carbon paste electrodes (CPEs) modified by carbon and lanthanide nano-materials were studied. Under the optimized conditions, the CPEs containing 5% of the reduced graphene oxide (RGO) decorated ceria (CeO2) nano-composite showed a significant increase in the response current toward sulfadiazine (SDZ) with respect to the other sulfonamide derivatives. A fast Fourier transform-square wave voltammetry (FFT-SWV) was applied in order to reveal the measurement applicability of the proposed electrode for the SDZ determination. The calibration curve result showed the linear range 3-1000 µM for the sulfadiazine redox. The LOD and LOQ quantities were calculated and compared with other reports in the literature. Furthermore, the SDZ measurement was carried out on some pharmaceutical tablets by the proposed sensor.