A new chalcogenide ion-exchanging material: Porous indium sulfide built from condensed [In 10S 18] 6− T3 supertetrahedral clusters

Abstract

A new open framework indium sulfide, In 10S 18[(H 2O) 4(C 6H 18N 4H 2) 1.5(C 6H 18N 4H 3)] (SCU-1), has been synthesized under hydrothermal conditions. X-ray diffraction (XRD), infrared spectra (IR), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and elemental analysis were employed for the characterization of SCU-1. The resultant crystallizes in the tetragonal space group P4 12 12 (No. 92) with a = b = 19.702(2) Å, c = 31.509(5) Å, V = 12,231(3) Å 3, and Z = 8. The crystal framework has a large pore volume of more than 51%. The charge balance of the anionic framework [In 10S 18] 6− is maintained by the template cations in the cavity spaces. The framework remained at higher crystallinity after about 90% of the extra-framework amines were removed by exchanging with K +. The as-synthesized material can undergo ion exchange with various metal cations in the selectivity series as Cu 2+ > Cr 3+ > Cs + > Zn 2+ > Co 2+ > Sr 2+ > Mn 2+ with the total ion exchange capacity (IEC) of 0.59 mmol/g.