Optoelectrical Switching of Nonfullerene Acceptor Y6 and BPQD‐Based Bulk Heterojunction Memory Device through Photoelectric Effect

The as‐prepared BPDQs:Y6:PVP blends, in which Y6 acts as nonfullerene acceptor, black phosphorus quantum dots (BPQDs) serve as donor, and polyvinylpyrrolidone (PVP) as a polymer matrix, can respond to both the electrical and optical stimuli. Using these blends as the active layer, the first bulk heterojunction device with the functions of organic photovoltaics and information storage, Al/BPQDs:Y6:PVP/indium tin oxide, is fabricated. When the applied voltages vary from 0 to −0.8 V, this device exhibits both the photoinduced resistive state changes and volatile photoresponse characteristic in the broadband visible region. The light illumination gives rise to the significantly decrease of the device resistance. Furthermore, it is also found that, when the applied voltages are changed from 0 to ± 3 V, this device shows a typical nonvolatile rewritable memory performance in the dark, with an ON/OFF current ratio of 8 × 103, a switching‐on voltage of −1.68 V, and a smaller switching bias window. Upon illumination with different wavelength light, both the switching‐on voltage and the ON/OFF current ratio of the device are found to be greatly decreased. This work can be expected to open a way to the integration of information storage, modulating and demodulating functions, photovoltaic effect, and photoelectric detection in an optoelectronic device. A novel electron donor–acceptor system composed of Y6 as nonfullerene acceptor and black phosphorus quantum dots (BPQDs) as donor is successfully constructed. The as‐fabricated Al/BPQDs:Y6:polyvinylpyrrolidone blend/indium tin oxide device can respond to both the electrical and optical stimuli.