Abstract: This study employed cross-linking units with star-like topology of varying sizes (ETPTA, POSS, and nano-zirconia) as cross-linking cores to chemically cross-link with poly(ethylene glycol) diacrylate (PEGDA), constructing three polymer networks (EP, PP, and ZP) for application in quasi-solid-state dye-sensitized solar cells (DSSCs). The results demonstrate that the strategy of increasing the size of the cross-linking core effectively enlarges the free volume of the polymer, reduces its glass transition temperature, and consequently enhances its low-temperature electrochemical performance. At a low temperature of -40 ℃, the power conversion efficiency (PCE) of the ZP-based device shows a significant increase of 37.4% compared to the EP-based device. This research provides a novel and effective strategy for developing quasi-solid-state electrochemical devices suitable for high altitude environment.

Key words: Quasi-solid-state dye-sensitized solar cells, Gel polymer electrolytes, Chemical cross-linking, Low temperature electrochemical performance