Donor-acceptor-donor it-conjugated material derived from merocyanine-diketopyrrolopyrrole: design, synthesis and photovoltaic applications

In this work, two diketopyrrolopyrrole based donors (DPP3 and DPP4) with an electron rich merocyanine as side arm conjugating with the electron-accepting DPP through different linking groups such as phenyl and thiophene, respectively. As a result DPP4, which is linked with thiophene, possesses significant red-shifted absorption. BHJ solar cells were fabricated using DPP3 and DPP4 as donor materials and the commercially available PC61BM as an acceptor moiety. It was observed that DPP4 gave less power conversion efficiency (0.4%) higher short-circuit current (J(SC)) 1.88 mA/cm(2) than the DPP3 with 0.48% power conversion efficiency with 1.72 mA/cm(2) J(SC). Our results suggest that the optical and electrochemical properties and photovoltaic performance of the DPP based BHJ devices can be influenced by the rational design of the DPP donor unit with merocyanine linkers.

Automated summary

This study investigated the impact of rational design of DPP donor units with merocyanine linkers on the optical, electrochemical properties, and photovoltaic performance of BHJ devices using DPP3 and DPP4 as donor materials and PC61BM as an acceptor moiety. The results showed that DPP4 had lower power conversion efficiency but higher short-circuit current compared to DPP3, indicating the importance of designing donor units for BHJ devices.