Photosensitized Thermoplastic Nano-Photocatalysts Active in the Visible Light Range for Potential Applications Inside Extraterrestrial Facilities

Abstract

Among different depollution methods, photocatalysis activated by solar light is promising for terrestrial outdoor applications. However, its use in underground structures and/or microgravity environments (e.g., extraterrestrial structures) is forbidden. In these cases, there are issues related to the energy emitted from the indoor lighting system because it is not high enough to promote the photocatalytic mechanism. Moreover, microgravity does not allow the recovery of the photocatalytic slurry from the depolluted solution. In this work, the synthesis of a filmable nanocomposite based on semiconductor nanoparticles supported by photosensitized copolyacrylates was performed through a bulk in situ radical copolymerization involving a photosensitizer macromonomer. The macromonomer and the nanocomposites were characterized through UV-Vis, fluorescence and NMR spectroscopies, gel permeation chromatography and thermogravimetric analysis. The photocatalytic activity of the sensitized nanocomposites was studied through photodegradation tests of common dyes and recalcitrant xenobiotic pollutants, employing UV-Vis and visible range (λ > 390 nm) light radiations. The sensitized nanocomposite photocatalytic performances increased about two times that of the unsensitized nanocomposite and that of visible range light radiation alone (>390 nm). The experimental data have shown that these new systems, applied as thin films, have the potential for use in indoor deep underground and extraterrestrial structures.

Abatement of Volatile Organic Compounds Employing a Thermoplastic Nano‐Photocatalyst Layered on a Glass Reactor

“…[22][23] In this context, the versatility of polymers has been exploited in several ways to produce photocatalytic nanocomposites. In particular, filmable photocatalytic nanosystems containing TiO 2 NPs [24] have shown high efficiency in the photodegradation of recalcitrant pollutants in aqueous media [25][26] and can be a valid alternative for the photo-oxidation of VOCs in gas-phase. Indeed, the filmability of the system makes it suitable to fit different shapes and surfaces, paving the way for novel depollution applications of air matrix.…”

Photocatalytic Activity of TiO2‐Containing Nanocomposites versus the Chemical Nature of the Polymeric Matrices: A Comparison

“…To overcome these limitations, several modifications are currently under investigation, such as metal and non‐metal doping, [ 7c,8 ] and coupling with other nanosystems. [ 9 ] In addition, the use of dye sensitizers [ 10 ] is a promising method for broadening light absorption into the visible light range. On the other hand, the development of three‐dimensionally ordered porous TiO 2 NPs has shown improvements in light‐absorption efficiency.…”

Effects of Simulated Solar Wind on Polymethyl Methacrylate Thin Film

“…Polymethyl methacrylate (PMMA) is a thermoplastic polymer with excellent mechanical properties, widely used for different applications, such as structural applications and also for windows and optical parts, due to its optical properties, e.g., glass [19]. Moreover, PMMA is simple to synthesize and can be used to produce polymeric-based nanocomposites possessing different characteristics and applications based on the used nanofiller [20][21][22][23][24]. PMMA is already widely used in form of thin film for the production of different types of electrical and optical devices [25,26], the preparation of superhydrophobic and antireflective glass surfaces [27], as well as the preparation of protective coatings when mixed with inorganic fillers [28], thanks to the ability to tailor its properties depending on the synthesis method and the surface modifications [29].…”