Enhanced Photocatalytic Hydrogen Production Activity by Constructing a Robust Organic-Inorganic Hybrid Material Based Fulvalene and TiO2

Abstract

A novel redox-active organic-inorganic hybrid material (denoted as H4TTFTB-TiO2) 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) (H4TTFTB) is an ideal electron-rich organic material and has been introduced into TiO2 for promoting photocatalytic H2 production under visible light irradiation. Notably, the optimized composites demonstrate remarkably enhanced photocatalytic H2 evolution performance with a maximum H2 evolution rate of 1452 μmol g−1 h−1, which is much higher than the prototypical counterparts, the common dye-sensitized sample (denoted as H4TTFTB-5.0/TiO2) (390.8 μmol g−1 h−1) and pure TiO2 (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 H4TTFTB and TiO2 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.

A Calcination‐Free Sol‐Gel Method to Prepare TiO2‐Based Hybrid Semiconductors for Enhanced Visible Light‐Driven Hydrogen Production

“…The light absorption of native‐TiO 2 was extended to the visible light range through organic doping, significantly enhancing its absorption capacity. This improvement is attributed to the presence of Ti−O‐C=O bonds in the NA−TiO 2 (2.5 wt %) material, which enabled native‐TiO 2 to absorb visible light (Figure S6) [17] …”

“…This improvement is attributed to the presence of TiÀ O-C=O bonds in the NAÀ TiO 2 (2.5 wt %) material, which enabled native-TiO 2 to absorb visible light (Figure S6). [17] The energy band diagram of native TiO 2 showed a single band gap of 3.2 eV, whereas the hybrid material NAÀ TiO 2 (2.5 wt %) displayed two distinct band gaps: a narrow band gap of 2.1 eV, corresponding to visible region absorption, and a wide band gap of 3.0 eV, corresponding to ultraviolet region absorption (Figure S11). The formation of TiÀ O-C=O in the hybrid material reduced the band gap of native TiO 2 , effectively decreasing electron-hole recombination to capture photogenerated electrons and enhancing the photocatalytic hydrogen production.…”

The acceleration of BODIPY dye-sensitized photocatalytic hydrogen production in aqueous ascorbic acid solutions using alkyl-chain formed second coordination sphere effects

“…21 Most of the donor (D)-p-acceptor (A) type BODIPY dyes are generally discussed by modulating and changing the functional groups at the a-, band meso-positions of the substituents to affect the activity. 22,23 On the other hand, the functionalization of the boron atom of BODIPY by uorine substitution of the boron-uorine bonding moiety can improve the stability of the dye by altering its electronic properties. 24 Few articles have investigated the effects of substituted F positions.…”

The Facile Synthesis of a Re-Complex Heterogeneous Catalysis System for Enhancing CO2 Photoreduction Activity

“…Functional materials with excellent optical physical chemistry performance can be obtained via an in situ sol–gel method containing hydrolysis and condensation reactions with the precursor of TiO 2 [ 33 , 34 , 35 , 36 , 37 ]. According to the previous achievements of our research group in the construction of functional composites [ 38 , 39 , 40 , 41 ], the hybrid nanomaterials displayed excellent light response ability and efficient photogenerated charge separation and transfer ability owing to the following advantages. First, the cross-linking of the photosensitizer and TiO 2 components in the hybrid materials at molecule level resulted in a uniform microporous/mesoporous structure to protect the photosensitizer molecules from falling off from the surface of TiO 2 .…”