The development of novel nanomaterials from semiconducting III-V elements became of utmost concern owing to the ability to tune their bandgaps for future application in optoelectronics comprising QLEDs and photon-managed solar cells. Gallium arsenide is a promising direct bandgap semiconducting material with high electronic mobility, rendering it suitable for optoelectronic devices. Here, we offer a novel method to synthesize Ga1-xDyxAs QDs using methylphenyldiamine-assisted hydrothermal approach for IR-laser diodes application. The XRD technique was employed to examine the crystal structures of the Ga1-xDyxAs QDs. The TEM technique was used to identify the shape and size of the Ga1-xDyxAs QDs. The UV–vis was utilized to emphasize the emission spectrum and bandgaps of Ga1-xDyxAs QDs. The PL measurements disclosed the capability of the Dy atoms to tune the emitted colors from the Ga1-xDyxAs QDs. Moreover, The Dy atoms acted as fluorescent centers which helped for the increase of the emitted light intensity and decreased its bandwidth. The Ga1-xDyxAs QDs exhibited a tremendous quantum yield of 81%. The developed IR-laser diode showed high responsivity and selectivity at 700 nm. Therefore, the Ga1-xDyxAs QDs showed promising optoelectronic performance for future IR-laser photodiode technological applications.