Enhanced Photocatalytic Hydrogen Production Activity by Constructing a Robust Organic-Inorganic Hybrid Material Based Fulvalene and TiO(2)

A novel redox-active organic-inorganic hybrid material (denoted as H(4)TTFTB-TiO(2)) based on tetrathiafulvalene derivatives and titanium dioxide with a micro/mesoporous nanomaterial structure has been synthesized via a facile sol-gel method. In this study, tetrathiafulvalene-3,4,5,6-tetrakis(4-benzoic acid) (H(4)TTFTB) is an ideal electron-rich organic material and has been introduced into TiO(2) for promoting photocatalytic H(2) production under visible light irradiation. Notably, the optimized composites demonstrate remarkably enhanced photocatalytic H(2) evolution performance with a maximum H(2) evolution rate of 1452 μmol g(−1) h(−1), which is much higher than the prototypical counterparts, the common dye-sensitized sample (denoted as H(4)TTFTB-5.0/TiO(2)) (390.8 μmol g(−1) h(−1)) and pure TiO(2) (18.87 μmol g(−1) h(−1)). Moreover, the composites perform with excellent stability even after being used for seven time cycles. A series of characterizations of the morphological structure, the photoelectric physics performance and the photocatalytic activity of the hybrid reveal that the donor-acceptor structural H(4)TTFTB and TiO(2) have been combined robustly by covalent titanium ester during the synthesis process, which improves the stability of the hybrid nanomaterials, extends visible-light adsorption range and stimulates the separation of photogenerated charges. This work provides new insight for regulating precisely the structure of the fulvalene-based composite at the molecule level and enhances our in-depth fundamental understanding of the photocatalytic mechanism.