Preparation of poly (ε‐caprolactone) as a gel electrolyte for dye‐sensitized solar cells

Abstract Substantially to increase the efficiency of dye‐sensitized solar cells (DSSCs), it has been fabricated with the polymer gel electrolytes (PGEs) by replacing the liquid electrolytes (LEs). Poly (ε‐caprolactone) (PCL) has been synthesized as a crystalline solid biopolymer of about 74% yield using different 6‐membered ring phenolate Al complexes. As prepared PCL was blended with LE used in dye‐sensitized solar cells (DSSCs) to prepare high polydispersity index (PDI) PGE. The prepared PGE shows cross‐linking between carboxyl and hydroxyl groups and interacts with iodide ions to form a chelate complex structure. The PGE was well‐characterized using various analytical tools to demonstrate its structural and surface morphology. The fabricated DSSCs using PGE showed high ionic conductivity (7.76 × 10 −4 S cm −1 ), good tri‐iodide diffusion (2.052 × 10 −6 Cm 2 S −1 ), and a highly stable incident photon‐to‐current conversion efficiency (PCE; 5.92%) under solar light illumination (85 mW cm −2 ). Besides found PGE has improved long‐term stability up to 15 days, and these results proved that the prepared PGE is superior compared to other reported PGEs.