Bimetal (Ni-Co) nanoparticles-incorporated electrospun carbon nanofibers as an alternative counter electrode for dye-sensitized solar cells

摘要

Counter electrode (CE) plays an important role in dye-sensitized solar cells (DSSCs). Electron transfer from external circuit to redox couple is mediated and facilitated by it to complete the DSSC circuit. Platinum (Pt) is widely employed as CE in DSSCs. However, due to its high cost and scarcity, efforts are being made to replace Pt. In this study, a bimetal (Ni-Co) nanoparticles-incorporated carbon nanofibers (CNFs) are prepared by electrospinning technique and used as CE material for DSSC applications. The morphology of prepared CNFs is characterized by field emission scanning electron microscope and transmission electron microscope studies. The structural properties are confirmed by X-ray diffraction and Raman spectroscopy studies. The electrochemical characterization of Ni-Co nanoparticles-incorporated CNFs is carried out using cyclic voltammetry, electrochemical impedance and Tafel polarization studies and compared with CNFs and std. Pt. The photo-conversion efficiency (PCE) of DSSC assembled with Ni-Co nanoparticles-incorporated CNFs as CE is very nearer to that of the same assembled with std. Pt as CE. Hence, Ni-Co nanoparticles-incorporated CNFs can be used as a cost-effective alternative CE for DSSCs.