Syntheses, crystal structure, and photoelectric properties of two selenoantimonates A-Zn-Sb-Se (A = Rb and Cs).

Metal chalcogenides, as a new class of semiconductor materials, have a broad range of applications in synthetic chemistry due to their rich structures and excellent properties. We have synthesized two selenoantimonates A 4 Zn 2 Sb 2 Se 7 [A = Rb(1), Cs(2)] under solvothermal conditions in the visible region using a band gap optimization strategy with alkali metals as structure-directing agents. Compounds 1 and 2 have a two-dimensional layered structure consisting of charge-balanced Rb + (1) or Cs + (2) cations and [Zn 2 Sb 2 Se 7 ] 4- anions with novel 20-membered rings (20-MR) [Zn 6 Sb 4 Se 10 ] with an aperture of 5.6949 × 13.7741 Å 2 formed in the middle. Furthermore, we have investigated the crystal structure, band gap, photoelectronic properties, and energy band structure.