Investigating potential properties of (8,0) Silicon Carbide Nanotube for applications in band gap tuning

Abstract

The changes in electronic and Magnetic properties of spin polarized silicon carbide nanotube (SiCNT), investigated using density functional theory and Quantum-Espresso computational package. In the present work, the electronic and magnetic properties of pristine, vacancy and transition metal(TM) doped (8,0) SWSiCNT are systematically investigated to give a detailed understanding of these materials. Magnetic moment were calculated, the electronic properties of zigzag (8,0) semiconductor silicon carbide nanotubes (SiCNTs) doped once at the time with Iron, Cobalt, Mnganse, Gadolinium and Hafinime. We have looked at the two possible scenarios where the guest atom X (Fe, Co, Mn, Gd, Hf), substituting in the Site of the Silicon atom X Si and carbon atom X C with different concentration, in the unit cell. We found that in the case of one atom Fe doped SiCNT, Co doped SiCNT, Mn doped SiCNT, Gd doped SiCNT and Hf doped SiCNT replacing a Silicon atom position annotated by Fe Si exhibits a magnetic moment of 1.99 μ B /cell and Mn Si exhibits a magnetic moment of 0.98 μ B /cell, Co Si exhibits a magnetic moment of 0.02 μ B /cell, whereas, in the case of two atom 2Fe doped SiCNT, 2Co doped SiCNT, 2Mn doped SiCNT, Gd doped SiCNT and Hf doped SiCNT replacing at two carbon atom position annotated by Fe Si exhibits a magnetic moment of 3.98 μ B /cell and Mn Si exhibits a magnetic moment of 1.99 μ B /cell, Also, two atom Cobalt replacing carbon, (CoC), induce a magnetic moment of 5.13 μ B and for three atom cobalt replacing Carbon 5.36. Substitution of three Cobalt in site of Silicon gives the maximum magnetic moment 9.00 μ B /cell but in contrast the calculated results show that the Co doping in Silicon carbide nanotube induces the ferromagnetism and metallic property for all concentrations.The calculated results show that the Mn doping in Silicon carbide nanotube induces the ferromagnetism and originates a half metallic (HM) gap at Fermi level (EF)in minority spin channel (MIC) for for 3.125 %, 6.25%, 9.37% and 12.75% concentrations. Moreover, the calculated results show that the Fe doping in Silicon carbide nanotube induces the ferromagnetism and Half Metalic property for 3.125%, 6.25% and 9.37% concentrations. Doping concentrations and dopant positions regulate the electronic structure and Magnetic property of the Silicon carbide nanotube, exhibiting both semiconducting and half-metallic behaviours as a response to the concentration of Transition Metals.