Red-Sensitive Image Array Based on Defect-Engineered PBDB-T/WSe1.5-WSe2/Graphene Heterostructure

2D transitional metal dichalcogenide (TMDC) materials have potential applications in image arrays for electronic eyes that mimick the human visual system. However, as a crucial requirement of the electronic eye, color discrimination is hard to achieve due to the broad absorption band of the TMDCs in the visible region. Here, a red-sensitive photodetector based on the defect-engineered WSe2-Graphene heterostructure covered by PBDB-T polymers is proposed. The WSe2-Graphene heterostructure is partially modified by defects generated by the focused ion beam, forming a photovoltaic diode at the boundary of the engineered region. Then, PBDB-T with optical absorption centered at the wavelength of 624 nm is coated onto the surface of the heterostructure, enhancing the photoresponse of the defect-engineered WSe2-Graphene to the red light (633 nm) ten times. Furthermore, a red-sensitive image array with 6 x 10 pixels is constructed. This work paves a novel avenue for developing the 2D color-resolvable photodetector array.