Study of the Electronic Properties of C20-nSin and C20-nGen (n=1-5) nano structures by the approach of Density Functional Theory

In this research, the thermodynamic stability, Energy of Gap and Electrical conductivity of nano structures of C20 bowl, C20-nSin (n=1-5) and C20-nGen (n=1-5) were investigated at the level of Quantum calculations of LSDA/6-31G of Density Functional Theory (DFT) at the room temperature. We have studied the application of these structures in solar cells. The most stable structures are C15Ge5 and C17Si3 at 300 K. The results show that the substitutes decrease gap of energy and increase the electrical conductivity, but the number of Silicon or Germanium substitute does not have the regular effect on the gap of energy. The C17Ge3 and C16Si4 have the lowest gap of energy and also have more conductivity. The gap of HOMO and LUMO energy levels of the electron donor and electron acceptor components is the most important factor for the electron transfer with photovoltaic application potential. The two structures of C17Si3 as electron acceptor and C15Ge5 as electron donor with the maximum voltage of 1.93 volt can be used in producing solar cell.