Electron Injection via Interfacial Atomic Au Clusters Substantially Enhance the Visible-Light-Driven Photocatalytic H₂ Production of the PF3T Enclosed TiO₂ Nanocomposite

Jui-Cheng Kao^1*, Dinesh Bhalothia², Zan-Xiang Wang², Hao-Wu Lin³, Fan-Gang Tseng², Li-Yu Ting⁴, Ho-Hsiu Chou⁴, Yu-Chieh Lo¹, Jyh-Pin Chou⁵, Tsan-Yao Chen²

¹Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
²Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
³Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan
⁴Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan
⁵Department of Physics, National Changhua University of Education, Changhua, Taiwan

* Presenter:Jui-Cheng Kao, email:zxww789987@gmail.com

A hybrid nanocomposite material, denoted as PF3T@Au-TiO₂, has been developed using atomic Au clusters, organic linear conjugated polymer, and inorganic semiconductor for visible-light-driven water splitting to produce H₂. At the heterogeneous interface, Au atoms, terthiophene groups, and oxygen atoms facilitate strong electron injection from PF3T to TiO₂, leading a significantly enhancement in H₂ production yield (18,578 μmol g⁻¹ h⁻¹). Density functional theory calculations reveal that intermediate states within the TiO₂ band gap generated from Au atoms enable the photoelectrons excitation from PF3T polymer to the conduction band of TiO₂. Charge analysis also proves that the atomic Au cluster and TiO₂ play the role of electron acceptor. As for the photocatalyst decorated with Au nanocluster, excess Au in-gap states serve as the recombination centers, substantially trapping the photoelectrons and thus inhibiting the hydrogen evolution performance.

Keywords: hydrogen production, visible–light-driven water splitting, Au nanoclusters, density functional theory calculation, titanium dioxide