<p>Understanding water adsorption on catalyst surfaces through DFT studies is essential for uncovering interaction mechanisms and enhancing surface reactivity. Defect modulation in oxide-based semiconductors like TiO₂ is pivotal for applications in catalysis, geophysics, and biochemistry. This study uses periodic DFT calculations to investigate water adsorption on Br- and N-doped TiO₂ (101) surfaces. The results indicate that Br and N doping enhances surface reactivity, yielding higher adsorption energy of -0.873&#xa0;eV for a single water molecule compared to -0.654&#xa0;eV for undoped TiO₂. An increase in the number of water molecules leads to cluster formation on the modified surface, demonstrating improved adsorption capability. Moreover, Br and N dopants facilitate water dissociation, suggesting an elevated radical’s production. This study is significant as it deepens our understanding of the surface behavior of doped oxide materials, i.e., TiO₂, paving the way for enhanced insights into their catalytic properties and potential applications in heterogeneous catalysis.</p> Graphical abstract <p></p>