Titanium dioxide is one of the most studied functional materials in current applied research. Thanks to its remarkable activity for heterogeneous photocatalysis under UV light, especially in the anatase form [1], TiO₂ has attracted broad interest for a wide range of applications. For example, the material can be successfully employed for the photodegradation of contaminants in water and air, the realization of self-cleaning surfaces, the production of antibacterial coatings or the manufacturing of sensors.

One of the most attractive approaches that can be potentially used to fabricate photocatalytic functional parts based on TiO₂ is 3D printing (also known as additive manufacturing). The advantages of this family of techniques over conventional subtractive manufacturing are widely acknowledged: optimal material usage, less design constrains, low cost, rapidity and high customizability of the final geometry. These attractive features can be combined with the photocatalytic properties of titania by loading the polymers used in 3D printing techniques like fused deposition modelling (FDM) or stereolithography (SLA) with TiO₂ nanoparticles [2].

In the present work, we investigate the SLA 3D printing of polymer-based composites containing different amounts of titania nanoparticles (2.5, 5 or 10 % wt.) and we evaluate their photocatalytic properties as a function of the amount of TiO₂ embedded. The 3D printability of the nanoparticle loaded resins and their rheological properties are evaluated as a necessary prerequisite for the 3D printing tests. Following 3D printing, the morphology and phase composition of the resulting composites are assessed. Finally, the pollutants photodegradation properties of the SLA printed titania nanocomposites are investigated by evaluating the photodegradation in water of the model molecule rhodamine B.

[1] K. Yaemsunthorn et al., ACS Appl. Nano Mater. 4, 633-643 (2021)
[2] A. D. McQueen et al., ACS ES&T Water 2, 137-147 (2021)