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 pi-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 x 1012 Jones, and an excellent on/off ratio as high as 3.37 x 104, for zero bias. At -2.0 V, under 365 nm illumination, the optimum R value was calculated as similar to 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.