Electronic and transport property of two-dimensional boron phosphide sheet

Investigating the thermoelectric properties of the (6, 6) two sided-closed single-walled boron nitride nanotubes ((6, 6) TSC-SWBNNTs) due to the impurity of a single carbon atom and temperature changes

In this research, the thermoelectric properties of the (6, 6) two sided-closed single-walled boron nitride nanotube ((6, 6) TSC-SWBNNT) was investigated in the state without impurity and carbon atom impurity instead of boron and nitrogen atoms in the center, left, and right the nanotube. The test conditions were the energy range of -5.5 to 5.5 eV and temperatures of 200, 300, 500, 700, 900, 1100, and 1300 K. Based on the obtained results, with an increase in temperature and the creation of impurities, the band gap is affected and becomes noticeably smaller. At the temperature of 1300 K, the band gap shows the greatest decrease and the peak height shows the least decrease. With increasing temperature, the number of peaks has decreased, suggesting an increase in the mobility of electrons and holes and a decrease in their localization. The Seebeck coefficient figures also changed by replacing carbon atoms with boron and nitrogen atoms in different parts of the nanotube. In addition, the height of the heat conduction peaks increased with increasing temperature. However, the heat conduction values are generally in the range of 9-10 nm, which are small values. With the increase in temperature, ZT values increased such that the highest values corresponded to the temperature of 1300 K. The ZT values higher than 1, especially at high temperatures, show that (6, 6) TSC-SWBNNT nanotubes are suitable candidates for thermoelectric materials.

DFT based investigations for the structural and electronic properties of coved zigzag BP nanoribbons

The peculiar properties of 2-D nano-materials have always inspired the research community for the further discovery of novel materials. Although III-V nitrides have been extensively explored for various remarkable phenomena, phosphides of the same group are yet to be explored. Taking a step in this direction, here we report the structural and electronic properties of zigzag BP nanoribbons (ZBPNR) with coved edge defects. The effect of sp² and sp³ edge passivation has also been compared to reveal interesting findings. The position of coved defect is considered in a number of different possibilities. It is observed that all the structures are energetically stable and maintain planar geometries. The H-passivated ribbons exhibit a semiconductor behavior with their band gap reciprocal to the ribbon width. However, for coved edge nanoribbons, a semiconductor as well as pure metallic nature has been predicted depending upon the site of the coved defect. Furthermore, the nature of the band gap is direct in H-passivated nanoribbons whereas for coved edges a direct to indirect alternation has been observed. The obtained wide range of electronic band gap (0.15 eV to 1.34 eV) indicates that ZBPNR could be useful for designing beyond silicon semiconductor devices.

Combined effect of stacking and magnetic field on the electrical conductivity and heat capacity of biased trilayer BP and BN

In this paper, the Kubo-Greenwood formula based on the tight-binding model is used to investigate the effects of the bias voltage and magnetic field on the electrical conductivity and heat capacity of the trilayer BP and BN with energy-stable stacking structures. The results show that electronic and thermal properties of the selected structures can be significantly modified by external fields. The position and intensity of DOS peaks and the band gap of selected structures are affected by the external fields. When external fields increases above critical value, the band gap decreases to zero and semiconductor-metallic transition occurs. The results show that the thermal properties of the BP and BN structures are zero in TZ temperature region and increase by temperature above TZ. The increasing rate for thermal properties depends on the stacking configuration and changes with the bias voltage and magnetic field. In the presence of the stronger field, the TZ region decreases below 100 K. Compared to the BP structures, the BN types with larger band gap has smaller electrical conductivity which can be increased in order to 3L-BP by applying the stronger magnetic field or bias voltage. These results are interesting for the future development of nanoelectronic devices.