Synthesis of a grafted cellulose gel electrolyte in an ionic liquid ([Bmim]I) for dye-sensitized solar cells

The cellulose was grafted homogeneously with acrylic acid by in situ polymerization in an ionic liquid 1-butyl-3-methylimidazolium iodide ([Bmim]I) as reaction medium. This polymer is suitable for quasi-solidification of electrolytes in DSSCs by in situ synthesis because the polymerization reaction proceeds in the ionic liquid containing iodide ion. Using the matrix as polymer host, KI and I2 as ionic conductors, an ionic conductivity of the gel polymer electrolyte was achieved 7.33 mS cm−1. Based on the optimized gel electrolyte, the best result of the quasi-solid state dye-sensitized solar cell (QS-DSSC) was the light-to-electricity conversion efficiency of 5.51% under a light intensity of 100 mW cm−2 (AM 1.5).