ZIF-67 derived CoS_x mediated 1D hollow carbon nitride for high photocatalytic hydrogen performance

Metal-Organic Framework (MOFs) consist of organic ligands having metal ions at the center that have many properties especially large surface area, polymetallic sites, tunable organic ligands, and porous structure. In this work, a three-dimensional MOF ZIF-67 was decorated over the g-C₃N₄ 1D hollow tubular structure by a simple precipitation technique. The proposed CoS_x co-catalyst was introduced as a free condition in the solution derived from ZIF-67 rather than loaded on the 1D g-C₃N₄. It is suggested that CoS_x offers an active site for the reduction of water molecules after accepting the photogenerated electrons from the 1D g-C₃N₄. The composite reveals high hydrogen performance (13911 μmol∙g⁻¹ h⁻¹) in comparison with ZIF-67 (4885 μmol∙g⁻¹ h⁻¹) and h-CN (1229 μmol∙g⁻¹ h⁻¹). Additionally, the composite sample has Quantum efficiency (Q.E) of about 19.5 % for hydrogen evolution reaction (HER) at 420 nm which is significantly greater than the h-CN (1.72 %) and ZIF-67 (6.87 %) sample. The work opened a new avenue in the field of photocatalysis by suggesting noble metal-free and high-efficiency MOF heterojunction.