“…The incorporation of Ag NPs was found to be able to narrow the band-gap energy of TiO 2 and create some plasmonic processes at the surface of TiO 2 , thus enhancing its antibacterial activity [25,26,27,28,29]. Typically, there are three routes to fabricating Ag/TiO 2 composites: the hydrothermal [30,31,32,33,34], photoreduction [23,35,36], and sol–gel [26,27,37] methods. The hydrothermal method can avoid the agglomeration of nanoparticles, but the required use of high temperature and high pressure to initiate the reaction often limits its value for industrial application.…”