Abstract
Three chalcogels KCrBiTe3, KZnBiTe3, and KFeBiTe3 were synthesized by the sol-gel metathesis route. K+ and the transition metal cations Cr2+, Zn2+ or Fe2+ connect [BiTe3](3-) anions to form amorphous black compounds. Supercritical drying of the black gels produced porous materials with BET surface areas of 230 m(2)/g (KCrBiTe3), 450 m(2)/g (KZnBiTe3) and 514 m(2)/g (KFeBiTe3). The adsorption properties of the resulting chalcogenide aerogels or chalcogels have been studied using volatile organic hydrocarbons (VOCs) and gases as adsorptives. The results show preferential adsorption of toluene vapor over cyclohexane vapor. The adsorption capacity toward toluene is 5.02 mmol/g for KCrBiTe3, 5.58 mmol/g for KZnBiTe3 and 7.89 mmol/g for KFeBiTe3. Preferential adsorption of CO2 over CH4 or H-2 was observed for the chalcogels: KCrBiTe3 (CO2/H-2: 175, CO2/CH4: 50), KZnBiTe3 (CO2/H-2: 180 and CO2/CH4: 60) and KFeBiTe3 (CO2/H-2: 225 and CO2/CH4: 65). (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.