LAUSR

Silicanes are predicted to be a candidate for next‐generation (opto‐)electronics nanomaterials. However, their low carrier or hole densities hinder their practical use in electronic materials. If conjugated substituents (e.g., electron donators or electron acceptors) could be attached to the surfaces of silicanes, these would be effective channel materials for phototransistors and exhibit the corresponding characteristic optoelectronic properties. Herein, the synthesis of silicanes modified by conjugated substituents is reported, and the performances of organo‐modified silicanes/graphene hybrid phototransistors are also evaluated. The room temperature hole mobility of the demonstrated phototransistors is ≈5 cm2 V−1 s−1. In this phototransistor, electron transfer from organo‐modified silicanes to graphene is observed after irradiation with visible light. This approach is applicable to other group IV elemental 2D materials, including germanane and stanane.