Interfacial electron transfer of P3HT/PDI/ZnO nanocomposite and its application in visible-light detection

Highlights: • Interfacial electron transfer (IET) plays a key role in photoactive organic/inorganic hybrid nanomaterials and remains elusive with regarding to interfacial energy level alignment. • In this study, high performance visible-light photodetector based on P3HT/PDI/ZnO has been fabricated with a high responsivity of 28.7 A W⁻¹ and an on/ off ratio as high as 217. • The excellent visible-light photoresponse of the hybrid device can be attributed to the enhanced interfacial contact after the modification of ZnO surface with PDI and the energetically staggered band alignment in the P3HT/PDI/ZnO hybrid system, which facilitate the exciton dissociate and charge transfer. Photoinduced interfacial electron transfer plays a key role in photoactive organic/inorganic hybrid nanomaterials and remains elusive with regard to interfacial energy level alignment. In this study, n-type organic semiconductor 1,6,7,12-tetrachloro-3,4,9,10-Perylenetetracarboxylicdiimide (PDI) molecules bearing carboxylic acid groups at nitrogen positions were grafted onto the surface of the Zinc oxide (ZnO) nanoparticles, and then blended with p-type poly (3-hexylthiophene) P3HT. The addition of PDI facilitates the charge transfer process from P3HT to ZnO, which was characterized by steady-state spectroscopy and time-resolved fluorescence spectroscopy. High performance visible-light detector based on P3HT/PDI/ZnO has been fabricated. This provides guidelines for the construction of optoelectronic devices.