Nano-sizing allows to control the physical properties of solids (e.g., melting point, chemical reactivity, catalytic activity, etc.). In semiconductors, nano-sizing allows tuning the band-gap value. Semiconductor band-gap control is very important in microelectronics since it allows device optimization for a specific application. For example, in optoelectronics, photosensors require band-gap values depending on the radiation to be revealed and the color of light-emitting diodes (LED) also depends on band-gap. Bulk molybdenum disulfide (MoS₂) band-gap is 1.2eV, while MoS₂ monolayers have 1.9 eV, which is a more convenient value for device fabrication.