Stannic-(Sn4+)-functionalizing of lithium cuprate composites towards CO2/NH3 capture at low temperatures
摘要
To decrease the levels of air pollutants as dispersed particles, hydrocarbons, CO, CO2 researchers exert much effort to formulate new gas capturing materials. Thus, the current research is presenting a novel, easy method for modifying and activating surface centers on lithium cuprate ceramics through compositing with stannic ions (Sn4+). A specific set of stannic ions (Sn4+-additions) was used to supplement the Li-sites in the Li-Cu-O system. At a sintering temperature of 860 °C and a slow annealing rate of 3ο/min, samples with the general formula Li1 + xSnxCuO2 were meticulously created via an advanced solid state reaction method (where x = 0.0, 0.025, 0.075, and 0.1 mol., respectively). Several analytical methods were used to thoroughly analyze the variation functionalized Sn-added samples. The unit cell dimensions were determined to be a = b = 2.29651, c = 14.7540 A° for the pure lithium cuprate. X-ray diffraction analysis revealed that all Sn-doped lithium cuprate samples primarily belong to the initially doubly trigonal crystal, which eventually has a hexagonal lattice structure with space group #166 (R 3 m). Additionally, stannic ions (Sn4+) in the tetra valence state were verified to exist by X-ray photo-emission spectroscopy (XPS). Microstructural characteristics, such as grain sizes and texture types, were investigated using 3D-atomic force microscopy (3D-AFM) and scanning electron microscopy (SEM). Furthermore, pure and variant functionalized Sn-added samples exhibited moderate to strong dual affinity as to serve as CO2/NH3 geses trappers. Kinetics and mechanisms of adsorption isotherms of gases trapping were proposed and discussed.