Hybrid silicon–carbon nanostructures for broadband optical absorption
Yang, Wen-Hua | Lu, Wen-Cai | Ho, K. M. | Wang, C. Z.
Proper design of nanomaterials for broadband light absorption is a key factor for improving the conversion efficiency of solar cells. Here we present a hybrid design of silicon–carbon nanostructures with silicon clusters coated by carbon cages, i.e., Siₘ@C₂ₙ for potential solar cell application. The optical properties of these hybrid nanostructures were calculated based on time dependent density function theory (TDDFT). The results show that the optical spectra of Siₘ@C₂ₙ are very different from those of pure Siₘ and C₂ₙ clusters. While the absorption spectra of pure carbon cages and Siₘ clusters exhibit peaks in the UV region, those of the Siₘ@C₂ₙ nanostructures exhibit a significant red shift. Superposition of the optical spectra of various Siₘ@C₂ₙ nanostructures forms a broad-band absorption, which extends to the visible light and infrared regions. The broadband adsorption of the assembled Siₘ@C₂ₙ nanoclusters may provide a new approach for the design of high efficiency solar cell nanomaterials.Show more [+] Less [-]