Clean chemical fuel (hydrogen) generation from water using heterogeneous photocatalysts is an emerging technology for sustainable energy research. However, photo-to-hydrogen conversion efficiency of benchmarking photocatalysts still appear to be far from practice due to their limited light absorption of solar irradiation spectrum (UV-vis-NIR) and poor excited carrier lifetime. There is, therefore, an increasing interest in developing high efficiency photocatalysts with a broad spectral response and efficient excited carriers separation. In this work, a novel MoS₂@TiO₂ heterostructured film with periodically patterned morphology, exhibiting an enhanced light absorption within UV-vis-NIR wavelengths, was developed. Both experimental studies and theoretical modeling demonstrate that S-vacancy in the multilayered MoS₂ nanoflakes is responsible for the localized surface plasmon resonance (LSPR, visible light absorption) and tunable band gaps (near infrared absorption). An outstanding H₂ yield rate of 580 mmol h^-1 g^-1 was then achieved using the rationally designed novel MoS₂@TiO₂ photocatalyst. Present study also shows that the developed catalyst can even split sea water under solar light irradiation, which will open a new paradigm for direct solar energy harvesting.