2021 Advanced Materials: 18.5% Efficiency Organic Solar Cells with a Hybrid Planar/Bulk Heterojunction

　　Advanced Materials recently published a study, by tailoring a hybrid planar/bulk structure, highly efficient organic solar cells (OSCs)  with reduced energy losses (E_losss) are fabricated.

　　The researchers inserted p-type benzodithiophene-thiophene alternating polymer and n-type naphthalene imide on both sides of a mixed donor: acceptor active layer to construct the hybrid heterojunction. Enlitech’s Solar Simulator and QE-R Quantum Efficiency Measurement system were used in this study. It was also equipped with certified standard silicon solar cell (SRC-2020) and EL-EQE system (ELCT-3010, now REPS) to assist in the measurement of experimental data. It was found that using the hybrid heterojunction architecture, photovoltaic characterization shows that the non-radiative E_loss is reduced by 25 meV, and the best OSC reaches 18.5% of high efficiency (certified as 18.2%). This means that the method in tailoring a hybrid heterojunction architecture is a great opportunity to finely optimize the detailed photovoltaic parameters and further improve the power conversion efficiencies (PCEs) for OSCs.