Synergistic Photocatalytic and Photothermal Antibacterial Activity of (In, Nb) and (Al, Nb) Co‐Doped TiO2 Ceramics

Abstract

Photodynamic and photothermal therapies are promising approaches to deal with implant‐associated infection. However, the efficacy of monotherapy is often insufficient, posing the importance of combinatory therapies. Herein, the AlNbTiO2 and InNbTiO2 ceramics are prepared by (In, Nb) and (Al, Nb) co‐doping into TiO2 ceramics via a solid‐phase reaction. The co‐doping enhances the visible/ near infrared (NIR) light adsorption and endows the TiO2 with excellent photocatalytic and photothermal properties, which is likely due to the formation of large defect‐dipole clusters and oxygen vacancies. The antibacterial efficacy of AlNbTiO2/InNbTiO2 ceramics is 99.04%/98.56% against E. coli and 95.06%/93.68% against S. aureus within 10 min under 808 nm NIR light irradiation, which is ascribed to the synergistic action of enhanced photocatalytic and photothermal effects. Cell culture experiments using MC3T3‐E1 cells prove that the viability and proliferation of MC3T3‐E1 cultured on TiO2 and AlNbTiO2/InNbTiO2 ceramics are comparable, emphasizing their excellent biocompatibility as well. This study suggests that AlNbTiO2/InNbTiO2 has potential application as an antibacterial bioceramic or coating for orthopedic implants.