The mechanism of enhanced charge separation and photocatalytic activity for Au@TiO₂ core-shell nanocomposite

ABSTRACT

The core-shell nanoparticles of Au@TiO₂ were synthesised via a simple and flexible hydrothermal route. The structure and properties were characterised by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, ultraviolet/visible diffuse reflectance spectra, photoluminescence spectra and Raman spectra. The photocatalytic activity and the photoelectrochemical behaviours were investigated. Compared to TiO₂, Au@TiO₂ exhibits superior photocatalytic activity and photoelectrochemical property. The enhanced properties of Au@TiO₂ attributed to the Au core as electron trap to promote the separation of photogenerated charge carriers in the photocatalytic process, which was also confirmed by the results of electrochemical impedance spectra and photoluminescence.

KEYWORDS:

• Au@TiO₂
• core-shell nanostructure
• photocatalytic property
• photoelectrochemical behaviour
• charge carriers

Acknowledgments

The authors thank for the support from the Analytical & Testing Centre, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, China.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Natural Science Foundation of China under Grant [Number 51802305]; Natural Science Foundation of Guangdong Province under Grant [Number 2018A030310134, 2018A0303130212]; and Science and Technology Planning Project of Guangzhou city, China under Grant [Number 201803030019].