High response organic ultraviolet photodetector based on bis (2-methyl-8-quinolinato)-4-phenylphenolate aluminum

We report highly efficient visible-blind ultraviolet photodetectors based on 1,3,5-tris(3-methylphenyl-phenylamino)-triphenyamine (m-MTDATA) as donor and bis(2-methyl-8-quinolinato)-4-phenylphenolate aluminum (BAlq) as acceptor. Strong photoluminescence quenching of m-MTDATA by BAlq is observed manifesting the efficient photoinduced charge transfer occurs between m-MTDATA and BAlq. The optimized device exhibits a photocurrent of 172 μA/cm2 at −14 V under an illumination of 365 nm UV light irradiation with an intensity of 0.691 mW/cm2, corresponding to a responsivity of 248 mA/W. We attribute the high response to the efficient electron transfer from the donor to the acceptor, the feasible level alignment match and the high carrier mobility of photoresponsive materials.