Optimising bifacial dye-sensitized solar cells with graphene-enhanced TPT configuration photoanode for operational stability

Abstract

Abstract Bifacial Dye-sensitized solar cells (bifacial DSSCs) are a promising low-cost and with promising light absorbance alternative to conventional DSSCs, known for their potential for transparency and customizability to be integrated into building-integrated photovoltaic (BIPV). This study explores enhancing efficiency and stability in bifacial DSSCs by integrating graphene into the bifacial configured photoanode. Graphene was incorporated into titanium dioxide ( $$\hbox {TiO}_2$$ ) photoanodes using a modified Ti-Nanoxide (T/sp) commercial paste, and powder type (P25) configurate as (T/sp-P25-T/sp) in tri-layer (identified optimal structure to maximizing bifacial light harvesting in our previous study) with Concentrations of 0.05%, 0.1%, and 0.2% graphene were tested. The structural, optical, and electrical properties of the materials were characterised using field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, Tauc plots, current-voltage (J-V) measurements, and electrochemical impedance spectroscopy (EIS). The incorporation of 0.1% graphene resulted in the highest initial power conversion efficiency (PCE) of 11.09% under combined front and back illumination at the 4th day of testing, indicating improved electron transport and stability. Over a period of ten days, the performance of these cells remained significantly superior compared to those with pure $$\hbox {TiO}_2$$ . These results highlight the potential of graphene-enhanced TPT-configured photoanodes for improving both the efficiency and durability of bifacial DSSCs, particularly in applications such as building-integrated photovoltaics.