Optimising processing conditions for the functionalisation of photocatalytic glazes by ZnO nanoparticle deposition

Abstract

ZnO nanospheres were synthesised and then deposited by both single- and double-fire fast processes on as-prepared ceramic substrates. The photocatalytic degradation of resazurin ink was tested under UV light. The single-fired samples did not show any evidence of photocatalytic activity because the nanoparticles melted during sintering at 1210°C. The double-fire ZnO spray-coating method successfully produced glazed materials with an active ZnO surface layer despite the high sintering temperature. The influence of experimental parameters, including the ZnO nanoparticle loading (0.03 to 1 mg/cm2) and firing temperature (650 to 800°C), were also investigated. Samples with a ZnO loading of 1 g/cm2 fired at 650°C showed the best photocatalytic activity. Increasing the temperature to 700 and 800°C led to the coalescence of ZnO nanoparticles, which reduced the photocatalytic activity.

Impact of Nanoparticle Additions on Life Cycle Assessment (LCA) of Ceramic Tiles Production

“…Several studies and patented researches have been carried out that have incorporated various types of nanoparticles, such as SiO 2 , Ge, TiO 2 , Cu, Au, Ag, Pt, Ti and Mg with the aim of improving the photocatalytic, antibacterial and self-cleaning properties of coating glazes [28][29][30][31][32][33][34][35][36][37][38][39], as well as enhancing the flexural strength of ceramic tile bodies through the addition of SiO 2 , PbO, Al 2 O 3 , Fe 2 O 3 , Ca, Na; Mg; B, Zn, Al and P nanoparticles [40][41][42][43][44].…”

“…Although nanoparticles have found applications in ceramic tiles, studies and patents are primarily focused on enhancing the photocatalytic, antibacterial, and self-cleaning properties of coatings [28][29][30][31][32][33][34][35][36][37][38][39]. However, some research on ceramic tiles has explored alternatives to improve the mechanical properties of the ceramic body, such as flexural strength by adding nanoparticles of Al 2 O 3 , SiO 2 , PbO, and Fe 2 O 3 [40][41][42][43][44].…”