Hybrid Nanostructures by Covalent Functionalization of MoS₂ and WS₂ with C₆₀ Undergoing Excited Electron Transfer

In this contribution, we report the formation, characterization, and photophysical assessment of hybrid nanostructures realized via a rapid and straightforward covalent functionalization reaction between MoS₂ or WS₂ and a modified C₆₀ bearing a 1,2-dithiolane chain. Transmission electron microscopy imaging analysis confirmed that the resulting hybrids are homogeneous at the nanoscale level, effectively suppressing undesired fullerene-fullerene aggregation. X-ray photoelectron and Raman spectroscopy evidenced the covalent connection between the two species, and thermogravimetry determined the loading of C₆₀ onto MoS₂ or WS₂. The MoS₂-C₆₀ and WS₂-C₆₀ hybrids were stable in liquid media, forming homogeneous inks, which enabled the investigation of thermodynamically feasible, excitonic electron transfer resulting in the formation of MoS₂ ^•+-C₆₀ ^•- and WS₂ ^•+-C₆₀ ^•- radical ion pairs by femtosecond transient absorption spectroscopy. The measured rates were found to be 1.92 × 10⁷ s^-1 for MoS₂-C₆₀ and 3.50 × 10⁷ s^-1, respectively, revealing their potential as light energy harvesting materials.