Decoration of γ-graphyne on TiO2 nanotube arrays: Improved photoelectrochemical and photoelectrocatalytic properties

A series of gamma-graphyne/TiO2 nanotube array heterostructures are first synthesized by a facile and environmental-friendly drop-coating method. The prepared heterostructures is completely investigated by a collection of characterizations. Interestingly, the unique C-O-Ti linkage between gamma-graphyne and TiO2 nanotube arrays is verified by both X-ray photoelectron spectroscopy and Fourier transform infrared analysis. After modification of gamma-graphyne, the maximum transient photo-current and photo-potential of TiO2 nanotube arrays are improved by 2.2 and 1.3 folds, respectively. Moreover, a maximum of 3.64 and 1.35 folds enhancements are severally verified for the photoelectrocatalytic degradation of levofloxacin and rhodamine B over the heterostructures compared to that of TiO2 nanotube arrays. Furtherly, the heterostructures also show superior photoelectrocatalytic performance on nitrogen fixation and oxygen evolution than TiO2 nanotube arrays. The crystal, morphological, photoelectrochemical, and photoelectrocatalytic stability of the heterostructures are confirmed. This work sheds light on designing gamma-graphyne modified composites for photoelectrochemical and photoelectrocatalytic application.

Automated summary

A series of gamma-graphyne/TiO2 nanotube array heterostructures were synthesized by a simple and environmentally friendly method. The modified heterostructures showed improved performance in photoelectrocatalytic degradation and nitrogen fixation, indicating great potential for applications in photoelectrochemical and photoelectrocatalytic processes.