Efficient photoelectrochemical water splitting of stainless steel electrocatalyst modified TiO2 films

Stainless steel (ST) is widely used in many different fields due to its low cost and excellent stability. However, the electrocatalytic property of ST film for water oxidation, especially combined with TiO2 photoanode, is seldom investigated. In this paper, we report a one-step sputtering strategy to synthesize ST film electrocatalysts on TiO2 film in order to boost the oxygen evolution reaction (OER) in water splitting. Compared to pristine TiO2 electrode, the ST modified electrode achieved a largely enhanced PEC performance. Such enhancement could be manipulated in an optimal manner when the ST film thickness was further varied, where the 80 nm ST modified TiO2 (ST-80-TiO2) showed the lowest overpotential of 132 mV, with the highest photocurrent density enhancements of nearly 18-fold and 11-fold under dark and simulated sunlight illumination, respectively. This facile and effective decoration approach makes it possible to design ST electrocatalyst-semiconductor structures for other general photoanode improvements. (C) 2019 Elsevier B.V. All rights reserved.