Dual-channeled organic-inorganic hybrid architecture: Leveraging a unique photosensitive semiconductor for enhanced photocatalytic hydrogen evolution

Broadening the spectral response to visible light and improving charge carrier mobility are key to increasing the efficiency of wide-bandgap semiconductors in photocatalytic water splitting for hydrogen production. This study introduces a cost-effective photosensitive organic photocatalytic semiconductor, Fluorescein (FL, C 20 H 12 O 5 ), and synthesizes the FL-Cu 1 Ni 2.5 -TiO 2 hybrid using a combined impregnation-photodeposition and electrostatic self-assembly strategy. The incorporation of CuNi bimetallic materials reduces costs, while hybridizing the photosensitizer (PSS) with the photocatalyst (PC) improves interfacial compatibility. This organic-inorganic hybrid exhibits a broad-spectrum response via photosensitization (PSS-PC), achieving efficient and stable photocatalytic hydrogen evolution under visible light (207.14 µmol/h). Moreover, FL also acts as an organic semiconductor, facilitating full-spectrum photosensitization and spatial carrier separation through the heterostructure. The dual-channel mechanism further enhances photocatalytic hydrogen evolution. Additionally, DFT calculations highlight the significant activity differences of FL-Cu 1 Ni 2.5 -TiO 2 in various electron donor environments. This research offers a promising new approach for enabling traditional wide-bandgap semiconductors to perform efficient photocatalytic water splitting under visible light by constructing an organic-inorganic hybrid system.