摘要： First-principles calculations have been carried out to investigate the stability, structural and electronic properties of two?dimensional hydrogenated GaAs with three possible geometries: chair, zigzag?line and boat con?gurations. The e?ect of van der Waals interactions on 2D H?GaAs systems has also been studied. These con?gurations were found to be energetic and dynamic stable, as well as having a semiconducting character. Although two?dimensional GaAs adsorbed with H tends to form a zigzag?line con?guration, the energy di?erences between chair, zigzag?line and boat are very small which implies the metastability of the system. Chair and boat con?gurations display a Γ?Γ direct bandgap nature, while pristine 2D?GaAs and zigzag?line are indirect semiconductors. The bandgap sizes of all con?gurations are also hydrogen dependent, and wider than that of pristine 2D?GaAs with both PBE and HSE functionals. Even though DFT?vdW interactions increase the adsorption energies and reduce the equilibrium distances of H?GaAs systems, it presents, qualitatively, the same physical results on the stability and electronic properties of our studied systems with PBE functional. According to our results, two?dimensional buckled gallium arsenide is a good candidate to be synthesized by hydrogen surface passivation as its group III?V partners two-dimensional buckled gallium nitride and boron nitride. The hydrogenation of 2D-GaAs tunes the bandgap of pristine 2D-GaAs, which makes it a potential candidate for optoelectronic applications in the blue and violet ranges of the visible electromagnetic spectrum.