A novel z-type heterojunctioned Ni₂O₃ composite catalyst for photocatalytic hydrogen generation

The development of an efficient and economically viable photocatalyst for hydrogen evolution reaction (HER) process is of paramount importance and holds considerable significance. Currently, high-performance catalysts predominantly incorporate precious metals, thereby substantially augmenting both cost and application complexity. This study explores a simple synthesized method and constructs various heterojunction structures in the HER catalyst via incorporating Ni₂O₃, TiO₂, and carbon nanotubes (CNT) to constitute the composite catalyst materials. Incorporation of Ni₂O₃ and CNT can form the z-type heterojunction, leading to a substantial enhancement in light absorbance and electron transmission capabilities, with the hydrogen production rate of 1422 μmol/g/h, which is 11-fold increase compared to that of TiO₂. The life cycle assessment (LCA) shows the total carbon footprint of this novel photocatalytic hydrogen technology is 81.91 kg CO₂-eq when producing 1 kg of hydrogen. The research presents a comparatively efficient and cost-effective photocatalytic material for hydrogen generation, offering valuable insights for future endeavors in this field.