Solar-driven hydrogen production via particulate photocatalysts is a sustainable and promising way for
overcoming the current energy crisis. In this work, CdS nanoparticles were synthesized via the
precipitation method and then decorated hydrothermally by NiMoO4 nanorods. The as-prepared CdSNiMoO4 nanocomposite showed an initial hydrogen generation rate (HGR) of 130 mmol h1 under the
visible spectrum. This represents a 7-fold increase compared to that of pure CdS. Increasing the
hydrothermal treatment temperature of the nanocomposite above 90 C was found to have a negative
impact on the H2 production efficiency. The prepared composite was subjected to various
photoelectrochemical measurements for investigating the photoelectric properties and the proposed
mechanism. The results revealed that CdS and NiMoO4 semiconductors have well-established band
structures to form a type-II heterojunction. Thus, NiMoO4 works as an electron collector that captures
the photogenerated electrons from CdS, thereby promoting the separation of e/h+ pairs. The
improvement in the catalytic performance could also be attributed to the increase in the active catalytic
sites of CdS-NiMoO4 (SBET ¼ 335.7 m2 g1) compared with CdS (SBET ¼ 225.5 m2 g1). Overall, this work
sheds light on using earth abundant NiMoO4 as an effective promoter in photocatalytic applications.