Efficient visible light-induced H2 production by Au@CdS/TiO2 nanofibers: Synergistic effect of core–shell structured Au@CdS and densely packed TiO2 nanoparticles

Abstract

Semiconductor-based photocatalysts for solar H2 generation has attracted significant attention because of its great potential for low-cost and clean H2 production. In this study, we prepared a core–shell structured Au@CdS on TiO2 nanofibers (Au@CdS/TNF) and investigated its photocatalytic H2 production under visible (λ>420nm) irradiation. Photocatalysts, including Au-deposited CdS/TNF (Au/CdS/TNF) and commercially available TiO2 (P25) instead of TNF, were investigated to determine the effect of a core–shell structured Au@CdS and the role of the TNF. Compared with CdS/TNF and Au/CdS/TNF, the Au@CdS/TNF exhibited strongly enhanced H2 production under visible irradiation. Furthermore, H2 production on Au@CdS/TNF was significantly enhanced compared to Au@CdS/P25. These results can be attributed to the synergistic effect of the core–shell structured Au@CdS and the compact structure of TNF. The core–shell structured Au@CdS may inhibit the formation of CdSO4 from CdS and the Au core could transfer electrons from CdS to TiO2 without any screening effect for light absorption by CdS. Moreover, interparticle electron transfer is more favorable for TNF than P25 due to the well-aligned TNF framework. This work demonstrates the synergistic effects of TiO2-based photocatalysts for the improvement of solar H2 production efficiency.