Microwave-assisted preparation of photoactive TiO2 on textile substrates

Abstract

Textiles are suitable substrates for photocatalytic materials such as titania, which can be introduced for different applications as wastewater cleaning or cleaning of air pollution. The actual investigation is related to the development of a microwave-assisted preparation of photoactive titania on textile substrates. The microwave application is part of a hydrothermal process which is used to promote the condensation of the titanium organic precursor to photoactive titania. The condensation of the precursor and therefore the preparation of titania is done directly on the textile surface, while the water and acid necessary for the condensation are transported via the gas phase to the textile. Photoactivity is determined by decomposition of organic dye (acid orange 7) under illumination with UV light. Further investigations are performed by scanning electron microscopy SEM, energy-dispersive spectroscopy EDS, and infrared spectroscopy. The determined photocatalytic effect of the realized titania materials strongly depends on the applied process temperature and also on process duration. Significant photoactivity is reached even after short processes of only 5 min and moderate process temperatures around 120°C. Under these mild process conditions, damaging the textile substrate during the preparation process is avoided.

Prospects for Further Development of Face Masks to Minimize Pandemics Functionalization of Textile Materials with Biocide Inorganic Nanoparticles: A Review

“…Lo anterior puede ser interesante cuando se evalúa el impacto de la morfología del sistema en la actividad contra diferentes microrganismos patógenos. Mahltig et al reportaron que una muy buena técnica para dispersar TiO 2 sobre textiles es por medio de impregnación hidrotermal asistida por microondas, la cual produce una muy buena dispersión de la fase activa [160]. En otro caso, Nazari investigó la síntesis de NPs de TiO 2 con tinte verde de cáscara de nuez por medio de impregnación asistida por ultrasonido, y obtuvieron un 100% de degradación de S. aureus y E. coli, lo cual fue atribuido a un efecto sinérgico entre el tinte y las NPs de TiO 2 [161].…”

Realisation of polyester fabrics with low transmission for ultraviolet light

“…To improve the application procedure, in addition, a solvothermal microwave-assisted process is used, which enables a significantly decreased process duration. 53 The actual investigated solvothermal microwave-assisted process enables process temperatures above 100°C, which is an improvement compared with microwave-assisted dyeing processes performed with polyester fabrics at 98°C or at the bp of the dyebath. 54,55 The use of the microwave-assisted solvothermal process has a significant advantage compared with the HT process, or with traditional dyeing processes with disperse dyes in general.…”

“…To achieve this, the dispersions of UV absorbers are also applied in HT processes. To improve the application procedure, in addition, a solvothermal microwave‐assisted process is used, which enables a significantly decreased process duration 53 . The actual investigated solvothermal microwave‐assisted process enables process temperatures above 100°C, which is an improvement compared with microwave‐assisted dyeing processes performed with polyester fabrics at 98°C or at the bp of the dyebath 54,55 …”

Rapid hybrid microwave cladding of SiO2/TiO2 sol–gel derived composite coatings

“…Several attempts have been made to synthesize sol-gel based SiO2/TiO2 coating on MW transparent polymer substrates by direct MW irradiation [16][17][18]. As the SiO2 and TiO2 coating materials coupled weakly with MW irradiation due to their low dielectric loss properties, heat generation was limited.…”