Surface Carbon Shell-Functionalized ZrO₂ as Nanofiller in Polymer Gel Electrolyte-Based Dye-Sensitized Solar Cells

We prepare dye-sensitized solar cells (DSSCs) fabricated with a poly (ethylene glycol) based polymer gel electrolytes (PGEs) incorporating surface carbon shell-functionalized ZrO₂ nanoparticles (ZrO₂-C) as nanofillers (NFs). ZrO₂ are polymerized via atom transfer radical polymerization (ATRP) using poly (ethylene glycol) methyl ether methacrylate (POEM) as a scaffold to prepare the ZrO₂-C through carbonization. The power conversion efficiency of DSSC with 12 wt% ZrO₂-C/PGEs is 5.6%, exceeding that with PGEs (4.4%). The enhanced efficiency is attributed to Lewis acid-base interactions of ZrO₂-C and poly (ethylene glycol), catalytic effect of the carbon shells of ZrO₂-C, which results in reduced crystallinity, enhanced ion conductivity of electrolytes, decreased counterelectrode/electrolyte interfacial resistance, and improved charge transfer rate. These results demonstrate that ZrO₂-C introduction to PGEs effectively improves the performance of DSSCs.