Functional Nanosheet Synthons by Covalent Modification of Transition-Metal Dichalcogenides

We report on the facile preparation of versatile MoS₂–thiobarbituric acid conjugates, which, in addition to excellent electrochemical behavior, can serve as nanosheet platforms for further functionalization in a multitude of applications. We show that chemically exfoliated MoS₂ was extensively modified with up to 50% surface coverage, while maintaining its metallic character, and that the strategy can be extended to MoSe₂, WS₂, and WSe₂. The covalent functionalization endowed the materials not only with good aqueous dispersibility, but also with improved hydrogen evolution reaction (HER) activity, as well as promise in the oxidative detection of DNA nucleobases in solution