Rapid synthesis, characterization, and antibacterial properties of ZnO-doped 3Y-TZP ceramics at low temperature with ultrafast densification

Because of their antibacterial and aesthetic properties, zirconia (ZrO 2 ) ceramics are gradually replacing traditional dental restoration metals and metal ceramic materials. Herein, densified 3 mol% Y 2 O 3 –stabilized tetragonal polycrystalline ZrO 2 (3Y-TZP) ceramics doped with ZnO , termed 3Y-TZP-x:Zn (x denotes the mass percentage of the ZnO functional agent), is rapidly prepared using spark plasma sintering (SPS). Results indicate that dense 3Y ceramics can be rapidly prepared via SPS at 1500 °C for 3 min, with a density of >99 % and the maximum doping content of the ZnO functional agent being 0.3 %. Scanning electron microscopy analysis shows that the 3Y ceramic is dense and the particles are uniform and small. This small particle size can enhance the diffusion of ZnO into bacterial cell membranes . 3Y-TZP-x:Zn (x = 0.1, 0.2, and 0.3) ceramics show certain antibacterial properties , with the antibacterial activity being strongest (74.55 %) at x = 0.3. The ZnO functional agent exerts antibacterial effects through a synergistic effect between (1) the contact adsorption mechanism by which reactive oxygen species are generated to inactivate the bacterial cell and (2) the dissolution mechanism by which the stability of metal cations in cells is destroyed. Therefore, SPS may be considered a promising technique for the preparation of antibacterial ceramics at lower temperatures.