Effect of alkali cations on two-dimensional networks of two new quaternary thioarsenates (III) prepared by a facile surfactant-thermal method

• NaAg2AsS3⋅H2O (1) and KAg2AsS3 (2) were prepared through surfactant-thermal method.
• Crystal structures show Na± and K± have different structure directing effects.
• The weak basicity of solvent is benefit to the growth of 2 compared with 1.
• Experimental and theoretical studies confirm 1 and 2 are semiconductors.

Two new quaternary thioarsenates(III) NaAg2AsS3·H2O (1) and KAg2AsS3 (2) with high yields have been successfully prepared through a facile surfactant-thermal method. It is interesting that 2 can only be obtained with the aid of ethanediamine (en), which indicates that weak basicity of solvent is beneficial to the growth of 2 compared with 1. Both 1 and 2 feature the similar two-dimensional (2D) layer structures. However, the distortion of the primary honeycomb-like nets in 2 is more severe than that of 1, which demonstrates that Na+ and K+ cations have different structure directing effects on these two thioarsenates(III). Both experimental and theoretical studies confirm 1 and 2 are semiconductors with band gaps in the visible region. Our success in preparing these two quaternary thioarsenates(III) proves that surfactant-thermal technique is a powerful yet facile synthetic method to explore new complex chalcogenides.

Two new quaternary thioarsenates(III) NaAg2AsS3·H2O (1) and KAg2AsS3 (2) with high yields have been successfully prepared through a facile surfactant-thermal method. X-ray single crystal diffraction analyses demonstrate that Na+ and K+ cations have different structure directing effects on these two thioarsenates(III). Both experimental and theoretical studies confirm 1 and 2 are semiconductors with band gaps in the visible region.Figure optionsDownload as PowerPoint slide