[01] Van Nghia Nguyen, Department of Physics, Quy Nhon University, Quy Nhon City, Viet Nam; Department of Physics, Hue University of Sciences, Hue City, Viet Nam. [02] Manh Son Nguyen, Department of Physics, Hue University of Sciences, Hue City, Viet Nam. [03] Minh Thuy Doan, Department of Physics, Quy Nhon University, Quy Nhon City, Viet Nam. [04] Nhat Hieu Hoang, Department of Physics, Quy Nhon University, Quy Nhon City, Viet Nam.

TiO₂ nanofibers (NFs) structures were fabricated on the indium tin oxide (ITO) conducting substrates that serve as working electrodes in photoelectrochemical (PEC) cells for the generation of hydrogen by water splitting. The TiO₂ -NFs were synthesized by the electrospinning method at room temperature using the spray solution of Titanium tetraisopropoxide and Polyvinylpyrrolidone polymer at different times spraying to optimize the water splitting efficiency. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS). The photoelectrochemical (PEC) properties of the electrodes were measured, using a three-electrodes electrochemical analyzer illuminated with a standard 150W Xenon lamp. It was found that maximum water splitting efficiency of TiO₂ -NFs electrode with spraying time at 20 min was about 0.03% (corresponding photocurrent density 80 μA/cm² at V_bias = 0.2 V). This result is relatively higher compared to TiO₂ nanostructures in previous studies.

Water Splitting, TiO₂ Nanofiber, Photoelectrochemical Cell, Electrospinning, Nanomaterials

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