This study investigates the implications of Sr doping upon the photoelectrochemical (PEC) water-splitting efficiency of WO 3 , utilizing both experimental and theoretical approaches. Sr-doped WO 3 films were synthesized hydrothermally. An extensive analysis was conducted to analyze the crystal structures, band edge, morphologies, band edge, electrochemical, and optical characteristics of Sr-doped films. The PEC investigations demonstrated that the Sr-doped WO 3 photoanode achieved a 3.6-fold enhanced photocurrent density of 1.62 mAcm -2 (at 1.23 V vs. RHE). Moreover, a maximum photocurrent density of 5.25 mAcm -2 was yielded in tartaric acid electrolyte. Incorporating Sr into the WO 3 lattice increased charge carrier density by lowering charge transfer resistance, leading to efficient charge separation, diffusion, and transfer properties. Remarkable photoconversion and charge separation efficiency values of 0.369 % and 79.8 % were obtained for Sr-doped WO 3 , respectively. Additionally, adding a hole scavenger observed a recorded photocurrent density value of 3.64 mAcm -2 . A stoichiometric evolution (2:1) of H 2 /O 2 gases with exceptional Faradaic efficiency of over 90 % was obtained after the Sr doping in WO 3 . In addition, density functional theory (DFT) calculations indicated an alteration to the bandgap and density of states, consistent with the experimental results, suggesting beneficial transformation for both the surface/bulk characteristics of WO 3 following Sr incorporation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Inc. All rights reserved.)