Free-Standing Two-Dimensional Ru Nanosheets with High Activity toward Water Splitting

The preparation of ultrathin ruthenium metal nanosheets is important because these materials have unique properties originated from the unique two-dimensional (2D) structure, and yet, it remains a synthetic challenge. Herein, we report the synthesis of free-standing 2D Ru nanosheets using a facile solvothermal method, in which Ru(III) is reduced via self-decomposition of the metal precursor and grows into ultrathin nanosheets with the aid of isopropanol and urea. The 2D Ru nanosheets and their 2D oxide derivative exhibit excellent hydrogen evolution reaction and oxygen evolution reaction activities, respectively. They show much enhanced properties compared with their Ru powder counterparts and the commercial Pt in electrolytic water splitting.