Oxygen vacancies (OVs) are one of the most critical factors
that
enhance the electrical and catalytic characteristics of metal oxide-based
photoelectrodes. In this work, a simple procedure was applied to prepare
reduced TiO2nanotube arrays (NTAs) (TiO2–x) via a one-step reduction method using NaBH4. A series of characterization techniques were used to study
the structural, optical, and electronic properties of TiO2–xNTAs. X-ray photoelectron spectroscopy confirmed
the presence of defects in TiO2–xNTAs. Photoacoustic measurements were used to estimate the electron-trap
density in the NTAs. Photoelectrochemical studies show that the photocurrent
density of TiO2–xNTAs was nearly
3 times higher than that of pristine TiO2. It was found
that increasing OVs in TiO2affects the surface recombination
centers, enhances electrical conductivity, and improves charge transport.
For the first time, a TiO2–xphotoanode
was used in the photoelectrochemical (PEC) degradation of a textile
dye (basic blue 41, B41) and ibuprofen (IBF) pharmaceutical using
in situ generated reactive chlorine species (RCS). Liquid chromatography
coupled with mass spectrometry was used to study the mechanisms for
the degradation of B41 and IBF. Phytotoxicity tests of B41 and IBF
solutions were performed usingLepidium sativumL. to evaluate the potential acute toxicity before and after the
PEC treatment. The present work provides efficient PEC degradation
of the B41 dye and IBF in the presence of RCS without generating harmful
products.