It is becoming increasingly important to consider physical dimensions in addition to chemical capabilities when designing material for a specific feature. The physical dimensions, optical properties, surface area, and mechanical properties of material all play a role in determining its photochemical capabilities. In 2D materials, the surface area for the photoelectric effect and the long-range conductivity for homogeneous charge distribution in the photochemical reactions are perfectly balanced. A wide range of 2D materials has been investigated to date: low-cost, stable, earth-abundant, and hazard-free. However, photocatalyst efficiency must be improved to meet modern society's growing green energy demand. Photocatalysts are particularly interested in storing solar energy in chemical bonds to provide long-term energy. Researchers from various fields have recently contributed to properly arranging photocatalytic reaction centers in space, tuning the bandgap by modifying physical structures and chemical functionalities, using machine learning protocol, and calculating DFT before preparing catalysts. This review will present the most recent contributions to modifying 2D materials to link the collective effort in developing photocatalysts for water oxidation. Furthermore, in the conclusion section, we will emphasize the ongoing work's perspective, challenges, and dimensions.