Nanopores in semiconducting oxides: optoelectronic and solar cell applications

Optoelectronic property of the semiconducting oxides has huge technological importance because high performance dye sensitized solar cell (DSSC) can be designed based on the loading of organic dyes (photosensitizers) inside the nanoscale pores, which could be an environment friendly alternative to fossil fuels as energy source. In a DSSC the dye molecule absorbs photon and injects electron to the conduction band of a semiconducting material. The electron is carried through the semiconductor matrix and flows to the counter electrode to give an electrical response. It is essential to know the different steps and mechanism of a DSSC involving nanoarchitectures of metal oxide photoelectrodes. In this review we have focused on discussing the working principle and gradual developments of DSSCs in the context of porous semiconducting oxide nanostructures. Efficiencies of different semiconducting electrodes along with their morphological features have been discussed. It has been seen that the efficiency of a DSSC depends largely on the dye molecule used for sensitization. Thus, discussion on different types of dyes has also been included.