Improved efficiency of ternary-blended films in organic solar cell

Organic solar cells (OSCs) have attracted great interest as next-generation energy sources. In this study, a diketopyrrolopyrrole (DPP)-based electron-rich small-molecule donor, α-DPP-DT, was incorporated into a P3HT:PCBM binary film to fabricate ternary-blended OSCs. The OSCs were fabricated with the conventional configuration of ITO/PEDOT:PSS/active layer/LiF/Al and exhibited a power conversion efficiency of 2.12 %, which was greater than those of the two corresponding binary-blended devices. Both the open-circuit voltage and short-circuit current density values of the ternary films were lay between the corresponding values of the two binary films. The proposed working mechanism of the ternary-blended films is based on an alloy structure of two donors rather than on a cascade structure.