Blended PQT-12 and PC61BM Thin Films Based Self-Powered and Fast Response Photodetector

Abstract

This letter reports a p-Type poly (3, 3''-dialkylquaterthiophene) (PQT-12) and n-Type [6, 6]-phenyl-C 61-butyric acid methyl ester (PC61 BM) bulk-heterojunction (BHJ) based self-powered photodetector. When monochromatic light is incident on the device, our proposed device shows a self-powered photodetection property with a significant enhancement of current by nearly 1000 times at zero bias condition due to synergistic effect of PQT-12 and PC61 BM. The self-powered nature of the proposed device is shown by measuring its optical characteristics over a wide wavelength range of 300-800 nm under zero-bias condition. The maximum responsivity of 167.5 mA/W, detectivity of \sim {4}\times {10}{{11}} cmHz {\text {1/2}} /W, and external quantum efficiency (EQE) of 41.6% are obtained at 515 nm under an incident light intensity of 57\mu \text{W} /cm2. The proposed BHJ photodetector gives a fast response with a rise time of 70 ms and a fall time of 100 ms. © 1980-2012 IEEE.