Natural rubber (Hevea Brasiliensis)-based quasi-solid electrolyte as a potential candidate for arresting recombination and improving performance in aqueous dye-sensitized solar cells

Abstract

We successfully fabricated dye sensitized solar cells (DSSCs) employing a quasi-solid state electrolyte based on pristine insulator natural rubber latex from Hevea brasiliensis and iodide electrolyte. Optimized devices exhibited a maximum power conversion efficiency (PCE) of 1.14% under simulated sunlight with 90 mW/cm2 illumination, 0.46% under 100 mW/cm2 and 7.85% under low intensity illumination of 1000 lx (Daylight LED). This gives a new perspective for the introduction of natural rubber latex abundant in nature as an additive to the water based redox mediator in order to improve the PCE in DSSC. A detailed study on the interfacial charge transfer in fabricated devices revealed that the introduction of rubber helped in arresting the back electron transfer, which was predominant in aqueous electrolyte based dye sensitized solar cell. This opens up opportunities for water-based electrolyte based on natural raw materials to be used in nature inspired DSSC technology.