Highly efficient organic-graphene hybrid photodetectors via molecular peripheral editing

Hybrid systems based on graphene and organic molecules are highly appealing for "correcting" the limited optoelectronic properties of 2D materials. However, an in-depth understanding of the correlation between the structure of the molecular sensitizer and the physical properties of the hybrid toward high-performance organic-graphene hybrid photodetectors remains elusive. Herein, an ad hoc molecular design via a peripheral editing approach on the organic molecules is employed to elucidate the structure-property relationship when interfaced with graphene forming hybrid systems. Efficient doping of graphene can be attained by physisorption of tetrathiafulvalene molecules exposing electron-donating peripheral groups, benefiting from a strong coupling yielding efficient charge transfer, ultimately leading to photodetectors with an ultra-high responsivity of 1.1 × 10⁷ A W^-1 and a specific detectivity of 6.5 × 10¹⁴ Jones, thereby outperforming state-of-the-art graphene-based photodetectors. These results offer valuable insights for future optimization of graphene-based photodetectors through molecular functionalization.