CoFe/CoFe2O4 Embedded N, S-Doped Carbon Hybrid Derived From Sulfonate Asphalt as an Efficient Counter Electrode for Quantum Dot Sensitized Solar Cell

Developing a sustainable and cost-effective counter electrode (CE) material with high catalytic activity is of significant importance for quantum dot-sensitized solar cells (QDSSCs). In this work, by using the industrial residue material of sulfonated asphalt as the carbon precursor, we prepared a CoFe/CoFe 2 O 4 embedded N, S-doped carbon hybrid (CoFe/CoFe 2 O 4 @C) and applied to the CE of QDSSC. Structure analyses indicated that CoFe/CoFe 2 O 4 @C has a porous structure with large surface area. Electrochemical investigations revealed that the CoFe/CoFe 2 O 4 @C possesses high catalytic activity for polysulfide reduction. Consequently, CdSe QDSSC based on CoFe/CoFe 2 O 4 @C CE achieved a high power conversion efficiency (PCE) of 6.37%, significantly superior to the commonly used PbS CE (5.4%). This study provides a sustainable strategy for converting the industrial residue material of asphalt into a low-cost and high-performance CE material for QDSSC.