Metal organic framework (MOF-5) and graphene oxide (GO) derived photoanodes for an efficient dye-sensitized solar cells

Abstract

In this work, graphene oxide (GO) and metal organic frameworks (MOF-5) have been used as adding materials in the modification of photoanode to enhance the photovoltaic performance of dye-sensitized solar cells (DSSCs). The photoconversion efficiency (PCE) is systematically examined in DSSCs, consisting of MOF-5 or GO incorporated TiO₂, GO/MOF-5 derived and pure photoanodes. The short circuit current density (J_SC) becomes higher after GO incorporating, resulting in improved PCE of the device compared with pristine one, due to its fast electron transport property. After the addition with GO/MOF-5, J_SC value gets close to that of pure one, due to suppression of electron transport, the photoelectron trapping at the interface. Moreover, adding with MOF-5 structure introduces better photovoltaic parameters with higher J_SC and open circuit voltage (V_OC) values, due to the high pore structure of MOF-5 material. Its property endues a high dye adsorption capability of MOF-5 modified photoanode, monitored by absorbance spectrum of dye-loaded one. The PCE of DSSC conducted with MOF-5 derived photoanode is 5.56 times superior to pure device, owing to improved light harvesting, and enhanced charge collection efficiency. The obtained results shed light on the important impact of derived photoanodes for DSSC applications in the future photovoltaic technologies.