Synthesis and characterization of TiO₂ foam and SiO₂@TiO₂ core‐shell nanostructure for gnetin dye degradation from industrial effluent

The current study intends to create TiO 2 foam, SiO 2 nanoparticles (NPs), and SiO 2 @TiO 2 core‐shell nanostructure (CSN) with improved photocatalytic durability for the quick degradation of the textile industrial water pollutant in the presence of sunlight. The sol‐gel, Stöber, and chemical co‐precipitation methods have been used to synthesize TiO 2 foam, SiO 2 NPs, and SiO 2 @TiO 2 CSN. X‐ray diffraction results have revealed the anatase phase of TiO 2 foam, the amorphous nature of SiO 2 NPs, and the amorphous nature of SiO 2 @TiO 2 CSN due to equal wt.% of SiO 2 NPs and TiO 2 foam at 300 K. Field emission scanning electron microscope images show that the TiO 2 foam, SiO 2 NPs, and SiO 2 @TiO 2 CSN exhibit cluster sheets, spherical, and spherical raspberry‐like homogeneous morphology. The ultraviolet spectrum confirmed that the TiO 2 foam and SiO 2 @TiO 2 CSN have a band gap of 2.9 eV and 3.4 eV. SiO 2 @TiO 2 CSN has been shown an excellent decomposition rate of water pollutants (gentian dye) in comparison to TiO 2 foam due to their better‐absorbing nature. Both NPs and CSN employed in the breakdown of gentian dye have been recycled and their original characteristics are preserved. The proposed SiO 2 @TiO 2 CSN has a higher potential for application in developing self‐cleaning, long‐lasting, and air‐purifying materials.