New Forms of CdSe: Molecular Wires, Gels, and Ordered Mesoporous Assemblies

• Published in: Journal of the American Chemical Society 2017-03, Vol.139 (9), p.3368-3377
• Main Authors: Hudson, Margaret H, Dolzhnikov, Dmitriy S, Filatov, Alexander S, Janke, Eric M, Jang, Jaeyoung, Lee, Byeongdu, Sun, Chengjun, Talapin, Dmitri V
• Format: Article
• Language: English
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.6b10077

This work investigates the structure and properties of soluble chalcogenidocadmates, a molecular form of cadmium chalcogenides with unprecedented one-dimensional bonding motifs. The single crystal X-ray structure reveals that sodium selenocadmate consists of infinite one-dimensional wires of (Cd2Se3) n 2n– charge balanced by Na+ and stabilized by coordinating solvent molecules. Exchanging the sodium cation with tetraethylammonium or didodecyldimethylammonium expands the versatility of selenocadmate by improving its solubility in a variety of polar and nonpolar solvents without changing the anion structure and properties. The introduction of a micelle-forming cationic surfactant allows for the templating of selenocadmate, or the analogous telluride species, to create ordered organic–inorganic hybrid CdSe or CdTe mesostructures. Finally, the interaction of selenocadmate “wires” with Cd2+ ions creates an unprecedented gel-like form of stoichiometric CdSe. We also demonstrate that these low-dimensional CdSe species show characteristic semiconductor behavior, and can be used in photodetectors and field-effect transistors.