TiO2/PFO inorganic-organic hybrid heterojunction for self-powered blue light photodetector

Organic-inorganic hybrid heterojunction is very promising for low cost and high performance photodetection device application. We have fabricated a heterojunction composed of n-type inorganic TiO _2 nanorod arrays and p-type organic semiconductor polymer [9,9-bis-(2-ethylhexyl)-9H-fluorene-2,7-diyl] (PFO). A peak of 0.32 mA W ^−1 was observed locating at 410 nm in spectral responsivity curve. The photocurrent response was rapid, repeatable as well as consistent. Under weak blue light (410 nm, 75 μ W cm ^−2 ) irradiance, the rise time and decay time were observed to be 0.16 and 0.12 s, respectively. These results demonstrated that TiO _2 /PFO heterojuncton could bring prospect for the development of self-powered blue light photodetectors with high spectral selectivity.