Abstract
Compositions and technology for obtaining a photocatalytic composite material (PCM) by deposition of titanium dioxide particles synthesized by the sol–gel method on a silica support of various types (microsilica, gaize and diatomite) have been developed. The properties (chemical and mineral composition, dispersion, specific surface area, porosity, ζ-potential, acid–base properties, and microstructure) of microsilica, gaize and diatomite were studied to assess the effectiveness of using a photocatalytic agent as a carrier. In terms of specific viscosity (ηsp = 45), the concentration of the precursor (tetrabutoxytitanium—TBT) is set at 22 vol. % in a solvent (ethanol), at which it is possible to obtain the maximum amount of dissolved film oligomer without the formation of an aggregate-like precipitate. Modification of the reaction mixture (precursor: ethanol = 1:3) by replacing part of the solvent with a Span-60 surfactant/TBT = 1–1.1 made it possible to obtain polydisperse titanium dioxide particles with peak sizes of 43 nm and 690 nm according to laser granulometry data. Taking into account the interaction of titanium complexes with the surface of a silica support, a phenomenological model of the processes of structure formation of a photocatalytic composite material is proposed. By the value of the decomposition of rhodamine B, the photocatalytic activity of the developed composite materials was determined: PCM based on diatomite—86%; PCM based on microsilica—85%; PCM based on gaize—57%.
Highlights
IntroductionAmong the numerous semiconductor photocatalysts, titanium dioxide (mainly in the polymorphic modification of anatase) occupies a special place due to its high photocatalytic activity, physical and chemical stability, non-corrosiveness, non-toxicity, availability and relatively low price [1,2,3,4]
Among the numerous semiconductor photocatalysts, titanium dioxide occupies a special place due to its high photocatalytic activity, physical and chemical stability, non-corrosiveness, non-toxicity, availability and relatively low price [1,2,3,4]
The aim of this work was to develop the composition of the raw mixture and the technology for the synthesis of a photocatalytic composite material with a self-cleaning function, which ensure the formation of nanosized anatase particles uniformly distributed on the surface of the silica support and a high photocatalytic activity of the final material
Summary
Among the numerous semiconductor photocatalysts, titanium dioxide (mainly in the polymorphic modification of anatase) occupies a special place due to its high photocatalytic activity, physical and chemical stability, non-corrosiveness, non-toxicity, availability and relatively low price [1,2,3,4]. One of the main goals of scientific research aimed at increasing the efficiency of the practical use of anatase is to improve its interaction with electromagnetic radiation (ultraviolet and visible) and adsorbed pollutants as a factor of high photocatalytic activity. This can be realized, for example, by: modifying the anatase structure by doping, achieving the nanoscale of its crystals, creating photocatalytic composite materials, etc. In this regard, from the point of view of the effectiveness of using anatase as a photocatalyst for construction, taking into account the large-scale industry of building materials, it is advisable to study the possibility of creating photocatalytic composite materials (PCMs). The research results show that an effective PCM for construction can be obtained by depositing titanium dioxide on a silica support [8,9,10,11,12,13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
