On the optoelectronic properties of non-covalently functionalized graphene for solar cell application

In this study, we report a simple approach toward the non-covalent functionalization of graphene by anthracene and thiophene molecules in different configurations, depending on the direction of the molecules approach to the surface of graphene. We examined structural, optoelectronic and vibrational properties of graphene before and after interaction with anthracene and thiophene. The density functional theory at B3LYP with 6-311G(d,p), 6-31G(d,p) and 6-31G(d) was employed to choose appropriate basis set that provides a more accurate molecular–properties description. This is important to compare and understand the deep relationship between the chemical structure of these heterostructures and their related properties to be chosen as an active layer in electronic devices. The device-based thiophene–graphene with perpendicular configuration film as an active layer in CdTe/CdS solar cell shows the best performance with a power conversion efficiency of \(9.58\%\), an open-circuit voltage of \(0.7\,\hbox {V}\), a short-circuit current density of \(24.47\,\hbox {mA}\,\hbox {cm}^{2}\) and a fill factor of \(55.92\%\) under simulated AM1.5 conditions at \(1000\,\hbox {W}\,\hbox {m}^{2}\).