Double wavelength ultraviolet light sensitive organic photodetector

The authors demonstrate an organic ultraviolet (UV) photodetector (PD) device in which 1,3,5-tris(3-methylphenyl-phenylamino)-triphenyamine and 1,3,5-tris(N-phenylbenzimidazol-2-yl)-benzene were used as the electron donor and acceptor, respectively. The PD diode offers responses of 75.2 and 22.5 mA/W as the 365 and 330 nm UV light with 1.0 mW/cm2 intensities illuminate the PD diode through anode and cathode sides, respectively. It is interesting that only the planar heterojunction structure diode can provide the special response feature while bulk-heterojunction device could not do it. The working mechanism of the PD diode was also discussed in detail.