Copper-based dye-sensitized solar cells with quasi-solid nano cellulose composite electrolytes

The study presented describes the preparation of solvent-free nano composite gel electrolytes in combination with copper(I)-based dye-sensitized solar cells (DSSCs). The electrolytes comprise poly(ethylene oxide) (PEO) and cellulose nano crystals (CNCs) and an I-3(-)/I- redox shuttle. The quasi-solid-state DSSCs show increased photoconversion performance with increased amount of CNC in the electrolyte. DSSC performances measured on the day that the devices are fabricated show that when the electrolyte is composed of 80% CNC, a cell efficiency of 1.09% is reached compared to 1.16% using a standard liquid I-3(-)/I- electrolyte. DSSCs containing the nano composites and the copper(I)-based dye show robust stability over time, and after 60 days, DSSCs with the PEO/CNC/I-3(-)/I- electrolyte outperform those containing the liquid electrolyte.