Tuning the optical and electrical properties of MoS₂ by selective Ag photo-reduction

Two-dimensional transition metal dichalcogenides have demonstrated potential for advanced electrical and optoelectronic applications. For these applications, it is necessary to modify their electrical or optoelectronic properties. Doping is one of the most prevalent techniques to modify the band structure of semiconductor materials. Herein, we report the p-type doping effect on few-layer and multi-layer MoS₂ that are selectively decorated with Ag nanoparticles via laser-assisted direct photoexcitation of MoS₂ exposed in AgNO₃ solution. This method can control the doping level by varying the duration of the laser irradiation, which is confirmed by the observed gradual rise of MoS₂ device channel resistance and photoluminescence spectra enhancement. This study demonstrated a simple, controllable, and selective doping technique using laser-assisted photo-reduction.