Woo Katherine E, Dolyniuk Juli-Anna, Kovnir Kirill
Department of Chemistry , Iowa State University , Ames , Iowa 50011 , United States.
Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States.
Inorg Chem. 2019 Apr 15;58(8):4997-5005. doi: 10.1021/acs.inorgchem.9b00017. Epub 2019 Apr 4.
Cs M SiAs (M = Cu, Zn, or Ga; y = 0.15-0.19; x depends on M) represents a new group of pseudo-two-dimensional compounds that allow property tuning with various metal substituents without alteration of the main Si-As two-dimensional framework. Their crystal structure is built from M SiAs layers separated by disordered chains of Cs cations. These compounds are synthesized using a CsCl flux as a source of Cs, circumventing the need for an expensive and air-sensitive Cs metal reagent. M-Si substitution is required to compensate for the excess electrons donated by Cs cations. Alternatively, the charge compensation can be achieved by the formation of As vacancies. Resistivity measurements confirm the electron-balanced nature of the compounds that exhibit semiconducting behavior with small bandgaps.
