Graphene oxide, a derivative of graphene, is a highly versatile and promising material with a wide range of potential applications in various industries. Its unique structure, which consists of a single layer of carbon atoms arranged in a two-dimensional honeycomb lattice, combined with oxygen-containing functional groups, gives graphene oxide distinctive properties that differentiate it from its pure form. Graphene oxide can also be used as a component in water treatment to adsorb pollutants. The synthesis of graphene oxide typically involves the oxidation of graphite flakes using strong oxidizing agents such as sulfuric acid and potassium permanganate. This process introduces oxygen-containing functional groups (such as hydroxyl, epoxy, and carboxyl groups) onto the graphene sheets, leading to the formation of a layered structure with sp2 and sp3 hybridized carbon atoms. Here, I present an overview of the study in atomic structure, synthesis, possible modifications, and applications of graphene oxide and reduced graphene oxide in optoelectronic devices, including our recent resulta in this field. According to this topic the following publications have been released: [1] S. Kumar, V. A. Dmitrieva, G. Meng, S. A. Evlashin, E. V. Sukhanova, D. G. Kvashnin, Z. I. Popov, A. G. Bannov, F. S. Fedorov, A. G. Nasibulin, ACS Appl. Nano Mater. 2023, 6, 14083. [2] N. D. Orekhov, J. V. Bondareva, D. O. Potapov, P. V. Dyakonov, O. N. Dubinin, M. A. Tarkhov, G. D. Diudbin, K. I. Maslakov, M. A. Logunov, D. G. Kvashnin, S. A. Evlashin, Carbon 2022, 191, 546.