Tremella-like Boron-doped hierarchical CN and dispersion Co phthalocyanine assembling heterojunction for photocatalytic hydrogen evolution

Semiconducting photocatalysts' electronic configuration significantly impacts their band gaps, charge carrier transport properties, and photocatalytic activities. Boron-doped tremella-like hierarchical CN and ultrathin Co phthalocyanine (CoPe) heterojunction (B1.5HCN-Co0.5%) formation via strengthened H-bonding interfacial connection possess excellent photocatalytic activities in water where the small amounts of catalysts exhibit a high photocatalytic H2 evolution activity with H2 evolution rate of 17818.82 μmol h−1 g−1 under simulated sunlight and 5558.81 μmol h−1 g−1 under visible light (≥420 nm). According to detailed characterization, the unique tremella-like hierarchical structure with abundant mesopores shortens the charge diffusion length. At the same time, incorporating CoPe improves the charge transport properties of B1.5HCN achieving effective spatial separation, which is primarily responsible for the improved performance. Both a significant amount of experimental data and theoretical calculations demonstrated the critical role of boron-doped and CoPe in photocatalytic H2 evolution. Heteroatom doping and heterojunction construction are essential in rationally regulating band structure to construct more efficient CN-based photocatalysts.