Investigating nickel foam as photoanode substrate for potential dye-sensitized solar cells applications

Abstract

In this work, replacing the glass/transparent conductive oxide combination with porous nickel foam is investigated. This approach has the main advantages of reducing losses due to spectral reflection, as well as significantly enhancing the conductivity of the electrode without adversely affecting its transparency. The electrode was tested optically to quantify its transmission, electrically to determine its sheet resistance, electrochemically to investigate its photoresponse and then will be used to construct a dye-sensitized solar cell. The projected benefit of such cells is the ability to design and build cells with any contour to fit façades or solar vehicles, as well as its suitability to host multiple cells that can be electrically connected in series or parallel to push further the concept of modular third generation solar cells. This is highlighted with the encouraging results of superior conductivity (lower sheet resistance) for the nickel foam of 0.00726 Ω sq−1 compared to 7.0599 Ω sq−1 for the FTO. Optically, the nickel foam is more absorptive across the visible range (400–800 nm). The latter exhibits the expected ∼20% reflectance loss, while the foam allows more opportunities to absorb incident radiation. Finally, a photoanode prepared using nickel foam with TiO2 and ruthenium dye was tested, and the charge transfer resistance as low as 667 Ωcm2 at the electrode/electrolyte interface is obtained, which is crucial for successful deployment in solar cell applications.