Investigation of the formation of fractal structures in SiO2 · SnO x · CuO y thin films prepared by the sol-gel method

Abstract

The processes of fractal structure formation have been considered in SiO 2 ⋅ SnO x ⋅ CuO y nanofilms pre pared by the sol-gel method from a tetraethoxysilane alchohol solution modified by metal salts. The atomic force microscopy images of these films have been obtained. The surface morphology has been analyzed using the Takens embedding method and Grassberger-Procaccia algorithm. The correlation and fractal dimen sions of the film samples and the coefficient of surface area increase have been calculated. The effects of the annealing temperature and concentration of the doping component on the formation of fractal structures in the materials under study have been estimated.

Experimental progress in positronium laser physics

“…Note that we refer to these materials as mesoporous (rather than nanoporous) following the convention of the International Union of Pure and Applied Chemistry: this classification defines microporous, mesoporous and macroporous materials as having pore diameters of less than 2 nm, between 2 and 50 nm, and larger than 50 nm, respectively. In powders the internal structure often has a fractallike dimensionality [285], and Ps emitted from the grains interacts with the surfaces of granular clusters. In mesoporous films, however, the situation is reversed, and the Ps interacts with the internal void surfaces.…”

Morphology-driven gas sensing by fabricated fractals: A review

“…The number L also characterizes fractal textures and quantifies the fractal-to-fractal gaps; the higher the lacunarity, the lower is the homogeneity [ 49 ]. In fractal studies, surface morphology, geometrical features, and degree of self-organization of materials are determined through these dimensionless numbers [ 50 ]. One of the most popular methods employed for determining fractal dimensions is the box-counting method.…”

“…Plugotarenko et al employed sol–gel method to prepare SiO 2 ·SnO x ·CuO y nanofilms from a tetraethoxysilane (TEOS) alcohol solution modified by metal salts and applied the samples for NO 2 sensing [ 50 ]. The SiO 2 ·SnO x ·CuO y films annealed at 500 °C exhibited a sample surface consisting of crater-like pits.…”

Impedance Spectroscopy of Hierarchical Porous Nanomaterials Based on por-Si, por-Si Incorporated by Ni and Metal Oxides for Gas Sensors

“…Fractal TiO 2 gas sensor has excellent performance in acetone detection, which attributed to the high film porosity and fractal like network structures [18]. The processes of fractal structure formation have been considered in SiO 2 /SnO x /CuO y nanofilms prepared by the sol-gel method [19]. Maximum NO 2 sensitivity appears at the ratio Sn/Cu = 6, when the processes of self-organization seem to be more active, resulting in transition of one type of fractal structure to another.…”