In situ synthesis of AgI on the nanosilica surface for potential application as a cloud seeding material

Abstract

A series of nanosilica/AgI composites was synthesized by in situ reactions between silver nitrate and ammonium iodide deposited on the nanosilica surface using the gas‐phase solvate‐stimulated mechanosorption modification (GSSMSM) under both dry and wet conditions. The characterization of the synthesized materials was performed by X‐ray diffraction (XRD), SEM/EDX (Scanning Electron Microscopy‐Energy Dispersive X‐ray), thermogravimetric (TGA) and gas sorption methods. As a result of the mechanosorption modification of nanosilica, the bulk density of the samples synthesized in the dry and wet medium increases from 45 g/l for initial nanosilica to 249 g/l and 296 g/l for the modified samples, respectively. The specific surface area of the composites decreased in compared to the nanosilica precursor. The SEM data showed a denser aggregate structure of the nanocomposites compared to the initial nanosilica. The XRD, SEM/EDX and TEM/EDX data indicated the formation of AgI clusters. The AgI particle size was in the range of 6‐45 nm. The ice‐forming activity of the AgI‐containing samples was examined as well. The sample with a smaller size of silver iodide on the surface exhibited superior ice‐forming properties, and considering the quantity of utilized AgI, the prepared samples hold promise for application in this field.