Polypyrrole‑molybdenum sulfide complex as an efficient and transparent catalytic electrode for bifacial dye-sensitized solar cells

A transparent catalytic counter electrode (CE) with excellent properties plays an important role in the performance improvement of bifacial dye-sensitized solar cells (Bi-DSSCs). In this work, pyrrole is combined with molybdenum sulfide (MoS2) by a refluxing technology and subsequently polymerized in situ to construct polypyrrole (PPy)-MoS2 CEs with high transparency. And compared with the original PPy CE, the PPy-MoS2 CE shows higher electrocatalytic activity for triiodide reduction. A superior power conversion efficiency of 9.48% under both-side irradiation is obtained for the Bi-DSSCs assembled with PPy-4 wt‰ MoS2 complex CE, compared to 7.36% bifacial efficiency for PPy-CE based solar cell.