Ultrafine M-doped TiO2 (M = Fe, Ce, La) nanosphere photoanodes for photoelectrochemical water-splitting applications

• Published in: Materials characterization 2019-06, Vol.152, p.188-203
• Main Authors: Rani, B. Jansi, Praveenkumar, M., Ravichandran, S., Ganesh, V., Guduru, Ramesh K., Ravi, G., Yuvakkumar, R.
• Format: Article
• Language: English
• Subjects: Photoelectrochemical water splitting; Solvothermal method; Ultrafine nanospheres
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2019.04.024

In this study, Fe-, Ce-, and La-doped TiO2 ultrafine nanospheres were synthesized via low-temperature solvothermal method. The structural and morphological variations of bare and M (Fe, Ce, La)- doped TiO2 were confirmed by X-ray photoelectron spectroscopy and transmission electron microscopy images. The fabricated photoanodes were tested using 1 M KOH electrolyte and demonstrated that they can be used for eco-friendly photoelectrochemical solar water-splitting application. Compared to bare TiO2 photoanodes, foreign cations (Fe, Ce, La)-doped TiO2-based photoanodes exhibited higher photocurrent response without bias. In nutshell, the rare-earth element La-doped TiO2 nanosphere photoanode showed good photocurrent response to approximately 0.48 mA/cm2 under illumination, with lower flat band potential shift of −0.83 V. The highest photostability of 96% was achieved over 2 h for 10% La-doped TiO2 nanosphere photoanode and was suitable for solar water-splitting applications. •Highest photostability of 96% is achieved over 2 h for 10% La-doped TiO2.•10% La-doped TiO2 nanospheres showed highest photocurrent response of 0.48 mA/cm2.•Lowest flat band potential of around −0.83 V with the negative shift was obtained.•Highest photostability over 7200 s with 96% of retention under irradiation