Ag2Se to KAg3Se2: Suppressing Order–Disorder Transitions via Reduced Dimensionality

• Published in: Journal of the American Chemical Society Vol. 140; no. 29; pp. 9193 - 9202
• Main Authors: Rettie, Alexander J. E, Malliakas, Christos D, Botana, Antia S, Hodges, James M, Han, Fei, Huang, Ruiyun, Chung, Duck Young, Kanatzidis, Mercouri G
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 25.07.2018; American Chemical Society (ACS)
• Subjects: ambient temperature; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; phase transition; semiconductors; silver; thermal conductivity; ultraviolet-visible spectroscopy; X-ray diffraction

We report an order–disorder phase transition in the 2D semiconductor KAg3Se2, which is a dimensionally reduced derivative of 3D Ag2Se. At ∼695 K, the room temperature β-phase (CsAg3S2 structure type, monoclinic space group C2/m) transforms to the high temperature α-phase (new structure type, hexagon...