S-1 SUPPORTING INFORMATION Nanoceria Supported Ruthenium(0) Nanoparticles: Highly Active and Stable Catalysts for Hydrogen Evolution from Water †‡ * †§ † † † Department of Chemistry, Middle East Technical University, 06800 Ankara, Turkey ‡ Department of Chemical Engineering and Applied Chemistry, Atılım University, 06830 Ankara, Turkey § Department of Chemistry, Faculty of Arts and Science, Sinop University, 57000 Sinop, Turkey E+mail addresses: serdarakbayrak.rg@gmail.com (S. Akbayrak), aonal@metu.edu.tr (A.M. Önal)