Recent increases in global energy demand have intensified the focus on clean and renewable energy sources, particularly hydrogen, which has seen rising demand over the last decade. However, low-emissions hydrogen production remains minimal due to high costs. Among promising alternatives, perovskite-type nanostructures like strontium titanate (STO) are considered effective photocatalysts for water splitting, with the limitation of absorbing light mainly in the UV spectrum. This limitation can be addressed by integrating it with ammonium vanadate bronze (NVO) and carbon dots (CDs). This work explores the synthesis and characterization of the heterostructure NH4V4O10/SrTiO3/CDs for hydrogen production, which is successfully synthesized using a hydrothermal method and characterized. Photoelectrocatalytic water splitting experiments revealed that the NVO/STO/CDs-2h electrode generates 19.9 μmol min−1 cm−2, four times more hydrogen under illuminated conditions than a non-modified electrode in darkness. Also, in photocatalytic experiments yields 6.7 μmol min−1 cm−2, 18 % more than NVO/STO/CDs-4h. This demonstrates that incorporating smaller CDs into the nanocomposite enhances light absorption, showcasing the potential of these materials for renewable energy applications.