This article reports the synthesis and photocatalytic H₂-generation of pristine and CdS-based hybrid photocatalysts. Acid-treated-multi-walled carbon nanotubes (a-MWCNTs) and colloids of the exfoliated two-dimensional MoS₂ nanosheets were used for the preparation of binary CdS/a-MWCNTs and ternary CdS/MoS₂/a-MWCNTs nanocomposites. Controlled exfoliation of as-synthesized bulk marigold flower-like MoS₂ to few-layer MoS₂ nanosheets shows a strong absorption and photoluminescence, indicating an indirect to direct bandgap transition. The visible-light photocatalytic H₂-evolution performance of the ternary nanocomposites was superior to that of the binary and pure photocatalysts. Transient photocurrent results revealed that the ternary nanocomposite exhibits a maximum photocurrent density of 11.12 mA/cm², which is 12 times higher than that of pristine CdS. This enhanced H₂-generation performance and photocurrent response is attributed to the CdS/MoS₂ heterojunction, which increases charge-separation efficiency of the composite. Furthermore, the presence of a-MWCNTs, as a co-catalyst/support, accounts for this excellent performance involving electron transfer from photoexcited CdS to MoS₂ edges through a-MWCNTs; this transfer results in enhanced charge separation. This enhanced charge-separation efficiency and photostability was demonstrated using a suitable mechanism, which was evident from photocurrent measurements and photoluminescence data. In such ternary hybrids, metal co-catalysts showed H₂-evolution activity with the following order: Pd > Ni > Au > Ag > Cu. This work further highlights the role of MoS₂/CNTs p-n junction embedded in CdS which serves as a promising heterojunction that promoted hydrogen production.