We report herein a versatile method for synthesis of nickel-based inorganic compounds (i.e., Ni–O, Ni–S, Ni–Se, and Ni–P) from one basic nickel-cyanide-bridged coordination polymer (Ni-CP) flakes via a straightforward one-step annealing operation. Thus obtained Ni-based cocatalysts have been loaded over TiO₂ via facile incipient impregnation method to investigate performance towards H₂ production via H₂O splitting reaction. Among examined compounds, the optimized 0.5Ni-P@TiO₂ exhibited the best photocatalytic activity with a hydrogen generation rate of 7.32 mmol h⁻¹ g⁻¹ compared with pristine TiO₂ (0.086 mmol h⁻¹ g⁻¹). While the 4Ni–Se@TiO₂ has revealed the strongest durability with cumulative hydrogen amount of 48.6 mmol g⁻¹ upon a 5-h reaction, which is 81-fold higher than TiO₂ at identical conditions. On the other hand, Ni–S, Ni–P, and Ni–O, impregnated with 0.5 wt% of titania, show 13, 46, and 49-fold enhancement in evolved H₂ amount higher than the bare titanium dioxide. Additionally, the mixtures have been investigated again through photo-electrochemical measurements confirming the outperforming performance of Ni–P@TiO₂ (0.5% wt). The processed synthesis methodology is economical and easy opening a door to synthesizing various transition metal compound/semiconductor composites for efficient water photocatalytic hydrogen generation.