Carbon-Incorporated NiO/TiO₂ Mesoporous Shells with p-n Heterojunctions for Efficient Visible Light Photocatalysis

Carbon-incorporated mesoporous NiO/TiO₂ (NiO/TiO₂/C) hybrid shells as low-cost and highly efficient visible light photocatalysts have been developed. The NiO/TiO₂/C hybrid shells were synthesized by choosing polystyrene nanospheres as templates, followed by TiO₂ and NiO coating, and finally the calcination post-treatment to carbonize PS with the aid of metal oxides. Polystyrene nanospheres serve dual purposes as both a template to ensure the hollow structure and the electrically conductive graphite carbon source. Evaluation of their photocatalytic activity by organic pollutes (rhodamine B, methylene blue, and phenol) degradation and H₂ production under visible light demonstrated the superior photocatalytic performance, thanks to the enhanced visible-light absorption and exciton separation associated with the incorporation of electrically conductive graphite carbon.