Abstract
Abstract The results of a comparative study of the compositions and structured of thin films deposited from film-forming sol–gel compositions based on SnCl4/EtOH/H2O and SnCl4/EtOH/H2O/NH4ОН precursors are presented. The surface morphology features and Sn, N, and Cl distributions in the film structure are analyzed, as well as the transparency of the films depending on the amount of ammonium hydroxide added to the sol–gel composition. Possible chemical processes and reaction products involved in film formation and crystallization are considered. The sizes and shapes of the resulting skeletal crystals are shown to depend on the amount of ammonium hydroxide added to the sol–gel system. Optical microscopy, electron microscopy, and X-ray powder diffraction show that nano- and microscale SnO2 crystals and NH4Cl-containing crystals are formed in the films studied. The newly gained data make it possible to control the morphology and composition of the synthesized thin films via the changing precursor ratio in sol–gel synthesis.