Covalent-bond editing by topochemistry of chalcogenide materials – COBEDIT

Stepwise construction of inorganic solids with precise control of its atomic-scale structural arrangements is one of major challenges in solid-state chemistry. A possible approach to achieve this goal is to develop a toolbox for cutting chemical bond only between targeted atoms retaining other structural fragments. The COBEDIT project aims at exploration of new functional materials using low temperature structural transformation by topochemistry of lamellar materials containing covalent anion-anion bonds. This topochemistry employs precursor materials in which anionic chalcogen oligomers are sandwiched between cationic sheets. These anionic moieties (Qn)2- (Q = S, Se) are found to be highly reactive with zerovalent metals leading to either intercalation of the transition metal cations into the host lattices or de-insetion of half of the chalcogen atoms upon the use of alkaline metals. Based on the topochemical reactions exploiting the concept of anion redox, the project will set up rational designs of new low-dimensional quantum materials as well as semiconductors potentially useful as optical or (photo)catalytic materials.