The effect of foamed cement nanocomposite as counter electrode on the performance of dye-sensitized solar cell

Improper interparticle connection between carbon-based materials, poor interface bonding between the carbon counter electrodes (CEs) and substrate, and low surface area are the main limitations of carbon-based CEs in dye-sensitized solar cells. In this study, we utilized foamed cement and binder for adherence and surface area improvement in carbon-based CEs, such as graphite, multi-walled carbon nanotubes, and carbon black (CB). The results revealed that incorporating foamed cement into carbon materials improved the resistance, short-circuit current density, fill factor, and power conversion efficiency of the device. The porous cement/CB nanocomposite CE with a photoconversion efficiency of 5.51% exhibited the best photovoltaic performance. Moreover, this nanocomposite electrode showed an enhancement catalytic activity by high current density in cyclic voltammogram, low charge transfer resistance $(R_{CT}$) in electrochemical impedance spectroscopy, and high exchange current density in Tafel measurements compared to other electrodes. The porosity of foamed cement has been found to be the main cause of its superior photovoltaic performance, which expands the contact area with the electrode and enables rich ion transport. Additionally, the enhanced performance was due to strong bonding, crack-free deposited films, superior conductivity, and high catalytic activity.