Thermal air oxidation of Fe: Rapid hematite nanowire growth and photoelectrochemical water splitting performance
RIS ID
104435
Abstract
Different iron oxide structures were formed by annealing of iron foils in air at temperatures between 500 °C to 800 °C. Depending on temperature, a significant variation in the hematite/magnetite ratio and a strongly temperature dependent morphology is obtained. While over a wide range of conditions more or less compact Fe 3O 4/Fe 2O 3 layers are obtained, at 600 °C rapid growth (several micrometer per hour) of highly crystalline hematite nanowires can be observed. Visible light photocurrent measurements in 1 M NaOH under AM 1.5 100 mW/cm 2 conditions show that photocurrent density and the onset potential for water oxidation strongly shifted in the cathodic direction for the nanowire morphology. The results indicate that a simple air oxidation of iron can provide a rapid path to form hematite nanowires. Obtained layers are considerably active as photoanodes for solar water splitting. 2012 Elsevier B.V. All rights reserved.
Publication Details
Grigorescu, S., Lee, C., Lee, K., Albu, S., Paramasivam, I., Demetrescu, I. & Schmuki, P. (2012). Thermal air oxidation of Fe: Rapid hematite nanowire growth and photoelectrochemical water splitting performance. Electrochemistry Communications, 23 (1), 59-62.