Green Synthesis of Silicon Carbide from Sugarcane Bagasse through Magnesiothermic Reduction: A Potential Biomaterial for Photovoltaic Solar Cell

Abstract

Sugarcane bagasse is the most abundant agricultural waste in terms of tonnage in the Philippines. This biomass can be converted into silicon carbide (SiC) – an important material for photovoltaic (PV) cells. SiC was prepared at 600 °C for 4 hours with the use of magnesium powder as a catalyst and it was further enhanced by doping through the solvothermal method. The successfully synthesized SiC appeared grayish in color having an average yield of 8.56%. The SiC was doped with varying amounts of urea (0.1, 1.0, 2.0, and 3.0, 0.02 M), an n-type dopant, and carried out in triplicate basis. Incorporation of n-type dopants increased its capability to be a good built-in voltage and absorbent of light. Effective band-gap energies of semiconductor material for the PV cells were in the range of 1.0-1.7 eV. Urea-doped SiC exhibited a higher wavelength compared with undoped SiC, which could imply their differences in bandgap. The conductance testing showed that electrical conductivity established a positive relationship with dopant concentrations. Appeared to be crystalline in nature, the surface morphology of doped and undoped SiC was determined through scanning electron microscope. The X-ray diffraction patterns confirmed the crystallinity of the synthesized material. The elemental analysis and vibrational frequencies through energy dispersive X-ray and Fourier transform infrared analyses proved the presence of silicon and carbon in the material. Therefore, sugarcane bagasse can be processed chemically to generate new products for solar cell applications employing simple and low-cost method.