Protecting TiS<sub>3</sub> Photoanodes for Water Splitting in Alkaline Media by TiO<sub>2</sub> Coatings
Nuria Jiménez-Arévalo, Eduardo Flores, Alessio Giampietri, Marco Sbroscia, Maria Grazia Betti, Carlo Mariani, F. Javier García-García, J.R. Ares, Fabrice Leardini, Isabel J. Ferrer
Abstract
High Resolution Image Download MS PowerPoint Slide Titanium trisulfide (TiS 3 ) nanoribbons, when coated with titanium dioxide (TiO 2 ), can be used for water splitting in the KOH electrolyte. TiO 2 shells can be prepared through thermal annealing to regulate the response of TiS 3 /TiO 2 heterostructures by controlling the oxidation time and growth atmosphere. The thickness and structure of the TiO 2 layers significantly influence the photoelectrocatalytic properties of the TiS 3 /TiO 2 photoanodes, with amorphous layers showing better performance than crystalline ones. The oxide layers should be thin enough to transfer photogenerated charge through the electrode–electrolyte interface while protecting TiS 3 from KOH corrosion. Finally, the performance of TiS 3 /TiO 2 heterostructures has been improved by coating them with various electrocatalysts, NiS x being the most effective. This research presents new opportunities to create efficient semiconductor heterostructures to be used as photoanodes in corrosive alkaline aqueous solutions.