(Keynote) Conduction and Photoconduction in Fullerene- and Porphyrin-Containing Metal-Organic Framework Thin Films

Abstract

Photoconductivity is a characteristic property of semi-conductors, enabling various applications such as photoresponsive transistors and light-sensing. Some crystalline metal-organic framework, MOF, composed of functional organic components show interesting photoconduction properties. Here, we compare the light-responsive conductivity of four different MOF thin films with similar structure, but different compositions, possessing C60 fullerene and porphyrin or phenyl moieties. The results show that the embedment of fullerene, as well-known n-conducting component, increases the conductivity but shows little photo-response. While the total conductivity values are small, the conduction in the porphyrin sample shows noticeable photo-response, in particular when exciting the Soret band with blue light. Taking advantage of donor-acceptor interactions, the combination of C60 and porphyrin in close proximity of the MOF structure, results in thin films with strong photo-response and conductivities increased by 2 orders of magnitude upon blue light irradiation.