Combining the screening by first-principles calculations and Born–Oppenheimer molecular dynamics simulations, we fully reconsider phosphorene oxidation and the formation of low-dimensional phosphorus oxides (PxOy). It is found that the previously reported 2-dimensional PxOy (2d-PxOy) structures cannot provide a full understanding of 2d-PxOy properties. We show that the P–O interaction can result in highly stable 0d-PxOy and 2d-PxOy structures with close energetics, but a noticeable difference in band-gap energies. Here, the possibility of the formation of amorphous 2d-PxOy structures and their unique electronic properties are also studied in detail.