Highly π-Conjugated, Heteroatom-Rich, Electron-Deficient Dibenzosuberenone–Pyridazine-Based System as a Promising Organic Semiconductor for Photodetection

Herein, we introduce a photodetector based on an organic–inorganic hybrid material. For this purpose, a highly π-conjugated, heteroatom-rich, and electron-deficient dibenzosuberenone–pyridazine-based organic semiconductor material, herein namely BDPDS-11, was rationally designed and successfully synthesized via an inverse electron-demand Diels–Alder (IEDDA) reaction. The molecular structure of the synthesized compound was fully analyzed using a combination of spectroscopic techniques, including 1H NMR, 13C NMR, FTIR, and mass spectrometry. The BDPDS-11 organic film was spin-coated onto a Si wafer to fabricate a p-BDPDS-11@n-Si p-n heterojunction device. The BDPDS-11@n-Si heterojunction photodetector demonstrated a broadband wavelength response from UV to Vis, a high D* value up to 1.70 × 1012 Jones, and an excellent on/off ratio as high as 3.37 × 104, for zero bias. At −2.0 V, under 365 nm illumination, the optimum R value was calculated as ∼3.60 A/W. Repeated I–V measurements 70 days after device fabrication showed that the heterojunction device exhibited excellent stability. The parameters of our hybrid photodetector are comparable to or even better than those of similar-purpose Si photodetectors. Our results demonstrate that the hybrid BDPDS-11@n-Si heterostructure is a promising candidate for low-cost, easy-to-fabricate, high-performance broadband photodetectors.