Abstract
AbstractA facile and eco‐friendly method for activating anodic TiO2 nanotubes (TNTs) by cyclic voltammetry (CV) is proposed, and photoelectrochemical properties of CV‐activated TNTs are compared with those of non‐activated TNTs and of TNTs activated by hydrogen‐thermal reduction. EPR and luminescence studies show that the pristine samples demonstrate rather large content of paramagnetic and luminescing defects, while hydrogenation and CV‐activation lead to the different type of rearrangement of defects. TNTs activated by CV‐Na2SO4 demonstrate significantly improved photocurrent density (2.25 mA cm−2) in comparison with that of the hydrogen treated and pristine ones (0.93 mA cm−2 and 0.31 mA cm−2) under NUV‐irradiation at 0.2 V (RHE). Enhanced photoactivity of Na2SO4‐activated TNTs correlates with higher luminescence quantum yield, lowest paramagnetic defects content and larger decay time of the luminescence. Thus, a decrease in the content of defects is an important factor that reduces the non‐radiative recombination of charge carriers. The activation‐induced redistribution of surface and bulk defects in nanotubes explains the increased photoelectrochemical activity of TiO2‐based anodes. Cyclic voltammetry has been proved to be a reliable method to increase the efficiency of TNTs in PEC water splitting.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.