Investigation of the Characteristic of Solution‐Processed Tetraphenyldibenzoperiflanthene (DBP) Film and Its Application on Organic Photovoltaic Cells

Abstract

Solution‐processed tetraphenyldibenzoperiflanthene (DBP) films are prepared with three popular solvents, including chroloform (CF), chrolobenzene (CB), and dichrolobenzene (ODCB). The absorption and photoluminescence (PL) spectra of the DBP solution and DBP film are investigated. The absorption spectra between the DBP film and DBP solution are similar, whereas the PL spectrum shape of the DBP film and DBP solution is completely different, originating from the DBP molecular aggregation in the film, causing conjugate expansion, which results in dimer luminescence. The DBP donor layer at 32 nm prepared from solvent of CF, CB, and ODCB achieves a power conversion efficiency (PCE) of 1.42%, 0.88%, and 0.48%, respectively. The annealing temperature and DBP thickness are optimized; the 32 nm‐thick active layer annealed at 50 °C achieves the highest performance. The CF‐DBP film represents an interpenetrating network morphology, slightly higher roughness and hole mobility, which may be the main contribution to the relatively higher photocurrent than the CB‐DBP and ODCB‐DBP devices. Herein, a simple guidance for preparing solution‐processed DBP films is provided and simultaneously its application on organic photovoltaic cells (OPVs) is expanded.