Novel NaNbO3-based, ferroelectric ceramics with excellent polarization and electric potential for antibacterial applications

Abstract

Low surface electric potential (<1V) limits the large-scale commercial application of ferroelectric antibacterial ceramics. We propose a strategy based on charge-balancing doping to enhance polarization and potential in NaNbO₃(NN)-based ceramics for disinfection application. The Mg²⁺ modified NN showed a superior bactericidal effect greater than 80 % for 1.5 h and 99.8 % for 3 h without heating or ultrasonication, which is superior to other published works. This is mainly due to its excellent surface electric potential of 1.72 V and defect-related discharge current of 141.9 pA compared to NN and Ca²⁺ modified NN. Ferroelectric properties demonstrated that NN-Mg possesses a lower E_C of ∼40 kV/cm and a higher P_r of ∼32 μC/cm². Furthermore, the combination of XRD, Raman shift, PFM, and permittivity testing suggests that the smaller domain and enhanced ferroelectric properties in NN-Mg originated from amphoteric doping. Finally, simulation results of the electric field distribution indicated that NN-Mg had a stronger attraction or repulsion to bacteria with negatively charged surfaces.