Bifunctional nanocomposites based on TixSn1-xO2 obtained by the protein sol-gel method using the microwave-assisted hydrothermal process

• Published in: Ceramics international 2024-12
• Main Authors: da Cruz Serejo, Raissa, Cabral Junior, Aluísio Alves, Rojas Nuñez, Alejandro Eusébio, Macedo Paiva, Antônio Ernandes, Sales de Oliveira, Sérgio Luís, de Andrade Monteiro, Cristina, Ferreira, Davi Souza, Mascaro Sales, Lucia Helena, Pereira de Figueredo, Gilvan, Gomes Rangel, José Hilton, Bezerra de Araújo Medeiros, Rodolfo Luiz, Oliveira, Marcelo Moizinho
• Format: Article
• Language: English
• Subjects: Microwave-assisted hydrothermal process; Nanocomposite; Nanoparticles; Protein sol-gel process; TixSn1-xO2
• ISSN: 0272-8842
• DOI: 10.1016/j.ceramint.2024.12.264

The microwave-assisted hydrothermal sol-gel method is a relatively new method of processing nanomaterials little used. This method stands out for its ability to produce highly pure homogeneous nanopowders in a short time at low temperatures. Studies involving this technique report more than one type of processing to obtain the desired material. However, in this work, the TixSn1-xO2 composite was obtained in one step. Therefore, the aim of this work was to synthesize, for the first time, nanocomposites based on TixSn1-xO2 (x = 0, 0.3, 0.5, 0.7 and 1) by the microwave-assisted hydrothermal protein sol-gel method in one step, using a protein precursor from a renewable source, rendering the method more environmentally friendly. The results obtained by XRD, Rietveld refinement, FTIR, TG/DSC, SEM-EDS, SEM-FEG, nitrogen physisorption analysis using the BET method and diffuse reflectance spectroscopy in the UV–Vis region indicated that TixSn1-xO2 nanocomposites can be obtained in up to 60 min at a temperature of 170 °C. The samples had a tetragonal rutile and anatase phase, with agglomerates of particles between 36.9 and 83.0 nm in size, inhomogeneous and in the shape of nanospheres an nanorods, and a surface area of up to 188.186 m2 g-1. It was observed that the band gap energy decreased as the concentration of TiO2 increased (3.67–3.04 eV). The photocatalytic activity of the nanocomposites was assessed by the photodegradation of the dye methylene blue (MB), showing a decolorization rate of up to 76 % in 160 min under UV-C irradiation. Antibacterial activity was checked by broth microdilution against standard strains of E. coli and S. aureus bacteria and all the samples showed antibacterial activity against the strains with a minimum inhibitory concentration (MIC) of up to 625 μg mL−1. These results therefore highlight the efficiency of the proposed method for obtaining bifunctional nanocomposites. TixSn1-xO2 nanocomposites synthesized at 170 °C by the microwave-assisted hydrothermal protein sol-gel method with photocatalytic and antibacterial activity. [Display omitted]