Highly Stable Self-Cleaning Paints Based on Waste-Valorized PNC-Doped TiO₂ Nanoparticles

Abstract

Adding photocatalytically active TiO 2 nanoparticles (NPs) to polymeric paints is a feasible route toward self-cleaning coatings. While paint modification by TiO 2 -NPs may improve photoactivity, it may also cause polymer degradation and release of toxic volatile organic compounds. To counterbalance adverse effects, a synthesis method for nonmetal (P, N, and C)-doped TiO 2 -NPs is introduced, based purely on waste valorization. PNC-doped TiO 2 -NP characterization by vibrational and photoelectron spectroscopy, electron microscopy, diffraction, and thermal analysis suggests that TiO 2 -NPs were modified with phosphate (P�O), imine species (R�N-R), and carbon, which also hindered the anatase/rutile phase transformation, even upon 700 °C calcination. When added to water-based paints, PNC-doped TiO 2 -NPs achieved 96% removal of surface-adsorbed pollutants under natural sunlight or UV, paralleled by stability of the paint formulation, as confirmed by micro-Fourier transform infrared (FTIR) surface analysis. The origin of the photoinduced self-cleaning properties was rationalized by three-dimensional (3D) and synchronous photoluminescence spectroscopy, indicating that the dopants led to 7.3 times stronger inhibition of photoinduced e − /h + recombination when compared to a benchmark P25 photocatalyst.

Facile Synthesis to Porous TiO2 Nanostructures at Low Temperature for Efficient Visible-Light Degradation of Tetracycline

“…The structure information of TiO 2 -100 was further investigated by Raman spectra. From the Raman spectrum in Figure 6 b, it can be seen that there were five typical Raman peaks at 145, 197, 398, 518, and 639 cm −1 within the range of 150–1000 cm −1 , which represented Ti-O single bond stretch vibration peaks in TiO 2 -100 crystal in the anatase phase, which is consistent with the previous reports by Maqbool et al [ 46 , 47 ]. This finding was in agreement with the XRD analysis results.…”

Functionalization of niobium nitrogen-doped titanium dioxide (TiO2) nanoparticles with ethanolic extracts of Mentha arvensis

“…The analysis confirmed the incorporation of nitrogen, phosphorus, and carbon-related species during synthesis. Upon integration into water-based polymeric paints, these NPs demonstrated significant photocatalytic activity, effectively removing 96% of surface-adsorbed pollutants under natural sunlight and UV radiation [ 10 ]. Recent advancements in functionalizing titanium dioxide (TiO2) nanoparticles (NPs) for biomedical applications have focused on enhancing their biocompatibility, targeting capabilities, and therapeutic efficacy [ 11 ].…”

Black TiO2 and Oxygen Vacancies: Unraveling the Role in the Thermal Anatase-to-Rutile Transformation

“…However, the criticality of the anatase-to-rutile transition remains a subject of intensive debate, primarily due to the varying transition temperatures and its reconstructive atom bond mechanism influenced by nanocrystal size, impurities, annealing temperature, and synthesis conditions [9,10]. As an example, very recently advanced characterization techniques such as ATR-FTIR, EELS, EFTEM imaging, XPS, Raman spectroscopy, and DRIFTS have confirmed the successful doping of the TiO 2 nanoparticles with nitrogen, phosphorus, and carbon [11]. This doping significantly enhanced the photocatalytic properties of the nanoparticles, as evidenced by their ability to inhibit electron-hole recombination by 7.3 times compared to the standard P25 photocatalyst.…”

“…This doping significantly enhanced the photocatalytic properties of the nanoparticles, as evidenced by their ability to inhibit electron-hole recombination by 7.3 times compared to the standard P25 photocatalyst. The doped nanoparticles resisted the anatase-to-rutile phase transformation, maintaining their anatase structure even after a calcination temperature of 700 • C [11]. On the other hand, the modification of the TiO 2 structure to form reduced black TiO 2 by oxygen vacancies not only narrows the band gap but also potentially alters the dynamics of the anatase-to-rutile transition [12].…”