Carbon-layer-coated TiO 2 /WO 3 nanofibers (WTC) were fabricated by combining the electrospinning technique (for TiO 2 /WO 3 nanofibers) and hydrothermal method (for carbon shell). The structure characterization results showed that TiO 2 /WO 3 nanofibers (WT) were encased within an uniform carbon shell about 10 nm in thickness. By adjusting the content of WO 3 , the graphitization degree of carbon layer could be controlled, and the WTC nanofibers had remarkable light absorption in the visible region. Furthermore, the photoelectrochemical performance and photocatalytic activity were investigated systematically. As expected, the H 2 -generation rate of the as-prepared composite materials was greatly enhanced compared with pure TiO 2 nanofibers (TNFs), TiO 2 /WO 3 nanofibers (WT) and TiO 2 @carbon core/shell nanofibers (TC). The enhanced activities were mainly attributed to the multichannel-improved charge-carrier photosynthetic heterojunction system with the carbon layer on the surface of TiO 2 as an electron collector and WO 3 as a hole collector, leading to effective charge separation on these components, which were evidenced by photoluminescence spectroscopy (PL), electrochemical impedance spectroscopy (EIS) and photocurrent analysis. Besides, the addition of WO 3 promoted the graphitization of carbon layer, which in turn improved transport of electrons in the carbon layer and also contributed to the performance improvement.
Advanced materials for photoelectrochemical H 2 production are important to the field of renewable energy. Despite great efforts have been made, the present challenge in materials science is to explore highly active photocatalysts for splitting of water at low cost. In this work, we report a new composite material consisting of 2D layered MoS 2 nanosheets grown on the presence of TiO 2 /WO 3 nanofibers (TW) as a high-performance photocatalyst for H 2 evolution. This composite material was prepared by a two-step simple process of electrospinning and hydrothermal. We found that the as-prepared TiO 2 /WO 3 @MoS 2 (TWM) hybrid exhibited superior photocatalytic activity in the hydrogen evolution reaction (HER) even without the noble metal-cocatalyst. Importantly, the TiO 2 /WO 3 @MoS 2 heterostructure with 60 wt% of MoS 2 exhibits the highest hydrogen production rate. This great improvement is attributed to the positive synergetic effect between the WO 3 and MoS 2 components in this hybrid cocatalyst, which serve as hole collector and electron collector, respectively. Moreover, the effective charge separation was directly proved by ultraviolet photoelectron spectroscopy, electrochemical impedance spectroscopy, and photocurrent analysis.
危险品化学品经营许可证（带存储）