The organic solar cells (OSCs) have been increasingly attractive due to their environmental issues, flexibility, economic advantages, designing and productions. First generation of these systems was commonly based on the fullerene structures. In this work, four donor–acceptor (D–A) systems using Sc-doped BN layer as the non-fullerene acceptor and alpha-sexithiophene as donor were investigated, and the efficiency of OSCs was assessed by application of density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculation methods. The results show that the systems were the superior by the highest and longest charge transfer from donor (D) to acceptor (A). According to the obtained results, two systems could just be applied as OSCs, which the highest anticipated voltage was 2.3 eV in them. Furthermore, the effective absorption range was about 100 nm in photoinduced electron transfer (PET) or charge transfer process at the end of ultraviolet (UV) region.