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Covalent organic frameworks (COFs) show promising prospect as the photocatalysts with advantages of exceptional light adsorption capabilities, large specific surface area, and adjustable band structure. However, COFs usually suffer from severe recombination of photogenerated carriers. Therefore, there is an urgent need to design effective COF-based heterostructures to enhance the separation of carriers. In this work, a porphyrin-based COF with electron donor-acceptor structure is synthesized viacondensation polymerization by using 5, 10, 15, 20-tetrakis (4-aminophenyl) porphyrin (TAPPP) and N, N, N, N-tetra(4-aldehydephenyl)-1, 4-phenylenediamine as the electron donor and acceptor, respectively. Subsequently, ZnIn2S4(ZIS) are successfully in-situgrown on the surface of porphyrin-based COF, forming a novel core-shell structure. The in-situ synthesized ZIS with positive charges can be easily adsorbed on the negatively charged sites of the COF’s surface via the electrostatic interaction. This organic/inorganic hybrid COF-ZIS heterostructure exhibits a superior photocatalytic hydrogen evolution (PHE) rate of 695 μmol g−1h−1, approximately three times higher than that of ZIS. The construction of COF-ZIS heterostructure played an important role in enhancing the separation and transport of photogenerated carriers, which provided more electrons at the surface of ZIS to take part in proton reduction. Electron paramagnetic resonance spectra confirm the charge carriers transfer mode in the COF-ZIS heterostructure via an S-scheme mechanism. Moreover, upon loading Pt as the cocatalyst, the heterostructure achieves an effective PHE rate of 2711 μmol g−1h−1along with an exceptional stability. Additionally, the COF-ZIS heterostructure reaches up to 2.45% of apparent quantum efficiency at 400nm. Notably, the average lifetime of the COF-ZIS heterostructure increases by 43.2% and 98.9% compared to that of ZIS and COF individually, as observed through single-particle fluorescence spectroscopy. This work gives valuable inspiration into the building of donor-acceptor COF-based S-scheme heterostructures to achieve highly effective green energy conversion by aligning band structures.

Photoinduced charge carrier separation derived by magnetic fields has attracted increasing attention for its ability to wireless regulate powder photocatalysts. In this study, carbon nanotubes (CNT) were used as network conductors to link ZnIn2S4nanosheets. The electron highway in CNT spontaneously enhanced the photoinduced charge carrier transfer between ZnIn2S4nanosheets. The photocatalytic H2evolution rate of the 3 wt % CNT-ZIS composite increased to ∼210 % compared to that of pure ZIS under 300 W xenon lamp illumination. Additionally, in a magnetic field with relative motion, the Lorenz force on photoinduced electrons and holes suppressed their recombination, while the motional electromotive force along CNT accelerated the electron transfer to surface active sites. Therefore, the photocatalytic H2evolution rate further increased to 290 %. The spontaneous and passive photoinduced charge carrier separation in CNT-ZnIn2S4network composites under a magnetic field contributed to enhanced photocatalysis. Moreover, CNT-based network semiconductor composites can be mass-produced at low cost. Magnetic field-enhanced photocatalysis can be universally achieved without limitation caused by intrinsic band structures.