Zinc phthalocyanine sensitized g-C₃N₄ photocatalyst for exceptional photocatalytic hydrogen evolution and pollutant degradation

Here in this manuscript, the high charge conductivity and exceptionally wide range soalr light absorption of metal phthalocyanines were followed for boosted photocatalysis. Graphitic carbon nitride, g-C₃N₄ (CN) was thermally prepared from melamine and loaded with appropriate amount of zinc phthalocyanine (ZnPc) to form ZPCN nanocomposites. The fabricated samples were used to liberate hydrogen from water and decompose 2,4-dichlorphenol (2,4-DCP) pollutant under visible-light irradiation. The optimized nanocomposite (0.5ZPCN) purchased highly accelerated photocatalysis and liberated 90 μmol H₂ in 1 h in the presence of methanol as sacrificial agent. The same nanocomposite also showed 85% decomposition efficiency for the degradation of 2,4-DCP pollutant. These enhanced catalytic activity of g-C₃N₄ functionalized with ZnPc are attributed to the exceptional visible light absorption and effective generation of super oxide ions and holes formed after charge transfer between g-C₃N₄ and ZnPc as confirmed from photoluminescence, fluorescent and electrochemical characterization of the nanophotocatalysts. The charge/radical trapping experiments confirmed that super oxide anions were the main oxidizing agents in the decomposition of 2,4-DCP.